Radio Link Monitoring/Radio Link Failure Reconfiguration Upon Bandwidth Parts Switching

ABSTRACT

A method in a user equipment (UE) (110) is disclosed. The method comprises obtaining (701) one or more radio link monitoring configurations, each radio link monitoring configuration associated with at least one bandwidth part. The method comprises determining (702) that the UE is to switch from a source bandwidth part to a target bandwidth part. The method comprises performing (703) radio link monitoring on the target bandwidth part according to an obtained radio link monitoring configuration associated with the target bandwidth part.

TECHNICAL FIELD

The present disclosure relates, in general, to wireless communicationsand, more particularly, to providing optimizations for reduced transmitpower control frequency operation.

BACKGROUND

In Radio Link Monitoring (RLM) handling in Long Term Evolution (LTE),the key question is how the user equipment (UE) generate In Synch (IS)and Out-of-Sync (OOS) events. One purpose of the RLM function in the UEis to monitor the downlink (DL) radio link quality of the serving cellin RRC_CONNECTED state. It is based on the Cell-Specific ReferenceSignals (CRS), which are associated to a given LTE cell and are derivedfrom the Physical Cell Identifier (PCI). When in the RRC_CONNECTEDstate, this enables the UE to determine whether it is in-sync orout-of-sync with respect to its serving cell.

The UE's estimate of the DL radio link quality is compared with OOS andIS thresholds (Qout and Qin, respectively) for the purpose of RLM. Thesethresholds are expressed in terms of the Block Error Rate (BLER) of ahypothetical Physical Downlink Control Channel (PDCCH) transmission fromthe serving cell. Specifically, Qout corresponds to a 10% BLER while Qincorresponds to a 2% BLER. The same threshold levels are applicable withand without discontinuous reception (DRX).

The mapping between the CRS based DL quality and the hypothetical PDCCHBLER depends on the UE implementation. However, the performance isverified by conformance tests defined for various environments.Additionally, the DL quality is calculated based on the reference signalreceived power (RSRP) of CRS over the whole band, since UE does notnecessarily know where PDCCH is going to be scheduled. This is becausePDDCH can be scheduled anywhere over the whole DL transmissionbandwidth, as described with respect to FIG. 1 below.

FIG. 1 illustrates an example of how PDCCH can be scheduled over thewhole DL transmission bandwidth. More particularly, FIG. 1 illustrates aplurality of radio frames 10, each having a duration of 10 ms. Eachradio frame 10 is made up of ten subframes 15, each subframe 15 having aduration of 1 ms. A UE performs one sample per radio frame 10 for RLM.As noted above, the DL quality is calculated based on the RSRP of CRSover the whole band since the UE does not necessarily know where PDCCHis going to be scheduled.

When no DRX is configured, OOS occurs when the DL radio link qualityestimated over the last 200 ms period becomes worse than the thresholdQout. Similarly, without DRX, IS occurs when the DL radio link qualityestimated over the last 100 ms period becomes better than the thresholdQin. Upon detection of OOS, the UE initiates the evaluation of IS.

In Radio Link Failure (RLF) modeling in LTE, the key question is how thehigher layers use the internally generated IS/OOS events from RLM tocontrol the UE autonomous actions when it detects that is cannot bereached by the network while in RRC_CONNECTED. In LTE, the occurrencesof OOS and IS events are reported internally by the UE's physical layerto its higher layers, which in turn may apply radio resource control(RRC)/layer 3 (i.e., higher layer) filtering for the evaluation of RLFas described in more detail in relation to FIG. 2 below.

FIG. 2 illustrates an example procedure for evaluating RLF. At step 201,the UE detects a first OOS event. At step 203, the UE detects up to N310consecutive out of sync events and starts timer T310 (as described inthe RRC specification 3GPP TS 38.331, portions of which are excerptedbelow). At step 205, timer T310 expires, and RLF occurs. The UEtransmitter is then turned off within 40 ms, and the RRCre-establishment procedure starts. The UE starts timer T311, and the UEsearches for the best cell. At step 207, the UE selects a target (i.e.,best) cell. At step 209, the UE acquires system information (SI) for thetarget cell and sends a random access channel (RACH) preamble to thetarget cell. At step 211, the UE acquires an UL grant and sends an RRCconnection reestablishment request message.

As noted above, the detailed UE actions related to RLF are captured inthe RRC specifications (3GPP TS 38.331). A portion of 3GPP TS 38.331 isexcerpted below:

 5.2.2.9 Actions upon reception of SystemInformationBlockType2  Uponreceiving SystemInformationBlockType2, the UE shall:   1> apply theconfiguration included in the  radioResourceConfigCommon;  . . .   1> ifin RRC_CONNECTED and UE is configured with RLF timers  and constantsvalues received within rlf-TimersAndConstants: 2> not update its valuesof the timers and constants in ue-   TimersAndConstants except for thevalue of timer T300;  . . .  5.3.10 Radio resource configuration 5.3.10.0 General  The UE shall:  . . .   1> if the receivedradioResourceConfigDedicated includes the rlf-  TimersAndConstants: 2>reconfigure the values of timers and constants as   specified in5.3.10.7;  . . .  5.3.10.7 Radio Link Failure Timers and Constantsreconfiguration  The UE shall:   1> if the receivedrlf-TimersAndConstants is set to release: 2> use values for timers T301,T310, T311 and constants   N310, N311, as included inue-TimersAndConstants received in   SystemInformationBlockType2 (orSystemInformationBlockType2-NB   in NB-IoT);   1> else: 2> reconfigurethe value of timers and constants in   accordance with receivedrlf-TimersAndConstants;   1> if the received rlf-TimersAndConstantsSCGis set to release: 2> stop timer T313, if running, and 2> release thevalue of timer t313 as well as constants n313   and n314;   1> else: 2>reconfigure the value of timers and constants in   accordance withreceived rlf-TimersAndConstantsSCG;  . . .  5.3.10.11 SCG dedicatedresource configuration  The UE shall:  . . .   1> if the receivedradioResourceConfigDedicatedSCG includes the  rlf-TimersAndConstantsSCG;2> reconfigure the values of timers and constants as   specified in5.3.10.7;  . . .  5.3.11 Radio link failure related actions  5.3.11.1Detection of physical layer problems in RRC_CONNECTED  The UE shall:  1> upon receiving N310 consecutive “out-of-sync” indications for  thePCell from lower layers while neither T300, T301, T304 nor T311 is running: 2> start timer T310;   1> upon receiving N313 consecutive“out-of-sync” indications for  the PSCell from lower layers while T307is not running: 2> start T313;  NOTE:Physical layer monitoring andrelated autonomous actions do not apply  to SCells except for thePSCell.  5.3.11.2 Recovery of physical layer problems  Upon receivingN311 consecutive “in-sync” indications for the PCell from  lower layerswhile T310 is running, the UE shall:   1> stop timer T310;   1> stoptimer T312, if running;  NOTE 1: In this case, the UE maintains the RRCconnection  without explicit signalling, i.e. the UE maintains theentire radio resource  configuration.  NOTE 2: Periods in time whereneither “in-sync” nor “out-of-sync”  is reported by layer 1 do notaffect the evaluation of the number of consecutive  “in-sync” or“out-of-sync” indications.  Upon receiving N314 consecutive “in-sync”indications for the PSCell from  lower layers while T313 is running, theUE shall:   1> stop timer T313;  5.3.11.3 Detection of radio linkfailure  The UE shall:   1> upon T310 expiry; or   1> upon T312 expiry;or   1> upon random access problem indication from MCG MAC while neither T300, T301, T304 nor T311 is running; or   1> upon indicationfrom MCG RLC that the maximum number of  retransmissions has beenreached for an SRB or for an MCG or split DRB: 2> consider radio linkfailure to be detected for the MCG i.e.   RLF; 2> except for NB-IoT,store the following radio link failure   information in theVarRLF-Report by setting its fields as follows: 3> clear the informationincluded in VarRLF- Report, if any; . . . 3> set theconnectionFailureType to rlf, 3> set the c-RNTI to the C-RNTI used inthe PCell; 3> set the rlf-Cause to the trigger for detecting radio linkfailure; 2> if AS security has not been activated: 3> if the UE is aNB-IoT UE: 4> perform the actions upon leaving RRC_CONNECTED asspecified in 5.3.12, with release cause ‘RRC connection failure’; 3>else: 4> perform the actions upon leaving RRC_CONNECTED as specified in5.3.12, with release cause ‘other’; 2> else: 3> initiate the connectionre-establishment procedure as specified in 5.3.7;  The UE shall:   1>upon T313 expiry; or   1> upon random access problem indication from SCGMAC; or   1> upon indication from SCG RLC that the maximum number of retransmissions has been reached for an SCG or split DRB: 2> considerradio link failure to be detected for the SCG i.e.   SCG-RLF; 2>initiate the SCG failure information procedure as   specified in 5.6.13to report SCG radio link failure;  The UE may discard the radio linkfailure information, i.e. release the UE  variable VarRLF-Report, 48hours after the radio link failure is detected, upon  power off or upondetach.  5.3.12 UE actions upon leaving RRC_CONNECTED  Upon leavingRRC_CONNECTED, the UE shall:   1> reset MAC;   1> stop all timers thatare running except T320, T322, T325, T330;   1> if leaving RRC_CONNECTEDwas triggered by suspension of  the RRC:  . . .   1> else: 2> releaseall radio resources, including release of the RLC   entity, the MACconfiguration and the associated PDCP entity for all   established RBs;2> indicate the release of the RRC connection to upper   layers togetherwith the release cause; . . .

The information element (IE) RLF-TimersAndConstants contains UE specifictimers and constants applicable for UEs in RRC_CONNECTED. The abstractsyntax notation one (ASN.1) for the RLF-TimersAndConstants IE is shownbelow.

-- ASN1START RLF-TimersAndConstants-r9 ::= CHOICE {  release  NULL, setup  SEQUENCE {   t301-r9  ENUMERATED {   ms100, ms200, ms300, ms400,ms600, ms1000, ms1500, ms2000},   t310-r9  ENUMERATED {   ms0, ms50,ms100, ms200, ms500, ms1000, ms2000},   n310-r9  ENUMERATED {   n1, n2,n3, n4, n6, n8, n10, n20},   t311-r9  ENUMERATED {   ms1000, ms3000,ms5000, ms10000, ms15000, ms20000, ms30000},   n311-r9  ENUMERATED {  n1, n2, n3, n4, n5, n6, n8, n10},   ...  } }RLF-TimersAndConstants-r13 ::= CHOICE {  release  NULL,  setup  SEQUENCE{   t301-v1310   ENUMERATED {    ms2500,  ms3000, ms3500, ms4000,ms5000, ms6000, ms8000, ms10000},   ...,   [[ t310-v1330  ENUMERATED {ms4000, ms6000} OPTIONAL -- Need ON   ]]  } }RLF-TimersAndConstantsSCG-r12 ::=  CHOICE {  release NULL,  setupSEQUENCE {   t313-r12  ENUMERATED {   ms0, ms50, ms100, ms200, ms500,ms1000, ms2000},   n313-r12  ENUMERATED {   n1, n2, n3, n4, n6, n8, n10,n20},   n314-r12  ENUMERATED {  n1, n2, n3, n4, n5, n6, n8, n10},   ... } } -- ASN1STOP

Table 1 below provides field descriptions for the RLF-TimersAndConstantsIE.

TABLE 1 RLF-TimersAndConstants field descriptions n3xy Constants aredescribed in section 7.4. n1 corresponds with 1, n2 corresponds with 2and so on. t3xy Timers are described in section 7.3. Value ms0corresponds with 0 ms, ms50 corresponds with 50 ms and so on. E-UTRANconfigures RLF-TimersAndConstants-r13 on1y if UE supports ce- ModeB. UEshall use the extended values t3xy-v1310 and t3xy-v1330, if present, andignore the values signaled by t3xy-r9.

Additional information about the timers and constants are provided inTables 2 and 3 below, respectively.

TABLE 2 Timers Timer Start Stop At expiry T301 Transmission of Receptionof Go to RRC_IDLE NOTE1 RRCConnectionReestabilshmentRequestRRCConnectionReestablishment or RRCConnectionReestablishmentRejectmessage as well as when the selected cell becomes unsuitable T310 Upondetecting physical layer Upon receiving N311 consecutive in-sync Ifsecurity is not activated: NOTE1 problems for the PCell i.e. uponindications from lower layers for the go to RRC_IDLE else: initiateNOTE2 receiving N310 consecutive out-of- PCell, upon triggering thehandover the connection re-establishment sync indications from lowerlayers procedure and upon initiating the procedure connectionre-establishment procedure T311 Upon initiating the RRC connectionSelection of a suitable E-UTRA cell or Enter RRC_IDLE NOTE1re-establishment procedure a cell using another RAT. T313 Upon detectingphysical layer Upon receiving N314 consecutive in-sync Inform E-UTRANabout the SCG NOTE2 problems for the PSCell i.e. upon indications fromlower layers for the radio link failure by initiating receiving N313consecutive out-of- PSCell, upon initiating the connection the SCGfailure information sync indications from lower layers re-establishmentprocedure, upon SCG procedure as specified in release and upon receiving5.6.13. RRCConnectionReconfiguration including MobilityControlInfoSCGNOTE1: Only the timers marked with “NOTE1” are applicable to NB-IoT.NOTE2: The behaviour as specified in 7.3.2 applies.

TABLE 3 Constants Constant Usage N310 Maximum number of consecutive“out-of-sync” indications for the PCell received from lower layers N311Maximum number of consecutive “in-sync” indications for the PCellreceived from lower layers N313 Maximum number of consecutive“out-of-sync” indications for the PSCell received from lower layers N314Maximum number of consecutive “in-sync” indications for the PSCellreceived from lower layers

When DRX is in use, the OOS and IS evaluation periods are extended inorder to enable sufficient UE power saving. In such a scenario, thelength of the OOS and IS evaluation periods depend upon the configuredDRX cycle length. The UE starts IS evaluation whenever OOS occurs.Therefore, the same period (TEvaluate_Qout_DRX) is used for theevaluation of OOS and IS. However, upon starting the RLF timer (T310)until its expiry, the IS evaluation period is shortened to 100 ms, whichis the same as without DRX. If the timer T310 is stopped due to N311consecutive IS indications, the UE performs IS evaluation according tothe DRX-based period (TEvaluate_Qout_DRX).

The whole methodology used for RLM in LTE (i.e., measuring the CRS to“estimate” the PDCCH quality) relies on the fact that the UE isconnected to an LTE cell, which is the single connectivity entitytransmitting PDCCH and CRSs.

In summary, RLM in LTE has been specified so that the network does notneed to configure any parameter (i.e., the UE generates IS/OOS eventsinternally from lower to higher layers to control the detection of radiolink problems). On the other hand, RLF/Secondary Cell Group (SCG)Failure procedures are controlled by RRC and configured by the networkvia counters (e.g., N310, N311, N313, N314 (which work as filters toavoid triggering RLF too early) and timers (e.g., T310, T311, T313 andT314).

The RLF parameters are configured in the IEs rlf-TimersAndConstants orradioResourceConfigDedicated IE. The rlf-TimersAndConstants IE can betransmitted in SystemInformationBlockType2 (orSystemInformationBlockType2-NB in Narrowband Internet-of-Things(NB-IoT)). The radioResourceConfigDedicated IE can be within RRCmessages such as RRCConnectionReconfiguration,RRCConnectionReestablishment or RRCConnectionResume, andRRCConnectionSetup.

The SCG Failure parameters are configured in the IEsrlf-TimersAndConstantsSCG, which can be transmitted in theRadioResourceConfigDedicatedSCG-r12 IE. TheRadioResourceConfigDedicatedSCG-r12 can be transmitted withinRRCConnectionReconfiguration.

In New Radio (NR), RLM is also defined for a similar purpose as in LTE(i.e., to monitor the DL radio link quality of the serving cell inRRC_CONNECTED state). Unlike LTE, however, some level of configurabilityhas been introduced for RLM in NR in terms of reference signal (RS)type/beam/RLM resource configuration and BLER thresholds for IS/OOSgeneration.

With respect to RS type/beam/RLM resource configuration, in NR two RStypes are defined for L3 mobility: Physical Broadcast Channel(PBCH)/Synchronization Signal (SS) Block (SSB or SS Block); and ChannelState Information Reference Signal (CSI-RS). The SSB basically comprisessynchronization signals equivalent to the Primary Synchronization Signal(PSS) and Secondary Synchronization Signal (SSS) in LTE andPBCH/Demodulation Reference Signals (DMRS). The CSI-RS for L3 mobilityare more configurable and configured via dedicated signalling. There aredifferent reasons to define the two RS types, one of them being thepossibility to transmit SSBs in wide beams and transmit CSI-RSs innarrow beams.

In RAN1# NR AdHoc #2, it was agreed that in NR the RS type used for RLMis also configurable (both CSI-RS-based RLM and SSB-based RLM aresupported). It seems natural that the RS type for RLM should beconfigured via RRC signalling. In RAN1 #90, it was agreed to supportsingle RLM-RS type only to different RLM-RS resources for a UE at atime.

As NR can operate in quite high frequencies (above 6 GHz, but up to 100GHz), these RS types used for RLM can be beamformed. In other words,depending on deployment or operating frequency, the UE can be configuredto monitor beamformed reference signals regardless of which RS type isselected for RLM. Hence, unlike LTE, RS for RLM can be transmitted inmultiple beams.

In the case of CSI-RS, the time/frequency resource and sequence can beused. As there can be multiple beams, the UE needs to know which ones tomonitor for RLM and how to generate IS/OOS events. In the case of SSB,each beam can be identified by an SSB index (derived from a time indexin PBCH and/or a PBCH/DMRS scrambling). In RAN1 #90, it was agreed thatthis is configurable and, in NR the network can configure by RRCsignalling, X RLM resources, either related to SS blocks or CSI-RS. OneRLM-RS resource can be either one PBCHSS block or one CSI-RSresource/port. The RLM-RS resources are UE-specifically configured atleast in case of CSI-RS based RLM. When the UE is configured to performRLM on one or multiple RLM-RS resource(s): periodic IS is indicated ifthe estimated link quality corresponding to hypothetical PDCCH BLERbased on at least Y RLM-RS resource(s) among all configured X RLM-RSresource(s) is above Q_in threshold; and periodic OOS is indicated ifthe estimated link quality corresponding to hypothetical PDCCH BLERbased on all configured X RLM-RS resource(s) is below Q_out threshold.There may also be a change in the number of RLM resources.

With respect to IS/OOS and BLER threshold configuration, the UE needs toknow which resources to monitor, as well as how to generate IS/OOSevents to be reported internally to higher layers. With respect to thegeneration of IS/OOS indication(s), in RAN1 #89 and RAN1 #90 it wasagreed that RAN1 plans to provide at least periodic IS/OOS indicationsand hypothetical PDCCH BLER is used as the metric for determining IS/OOSconditions for both PBCH/SS block-based and CSI-RS-based RLM.

Unlike LTE, in which the signal-to-interference-plus-noise ratio (SINR)maps to a 10% BLER for the generation of OOS events and the SINR maps toa BLER of 2% for the generation of IS events, configurable values can bedefined in NR. In RAN1 #90 it was agreed that NR supports more than onein-sync BLER value(s) and out-of-sync BLER value(s) for a hypotheticalPDCCH, although in RAN1#AdHoc it was agreed that a single IS BLER andOOS BLER pair can be configured at a time for a UE, from two possiblepairs of values (to be decided by RAN4). Hence, unlike LTE, the BLERthresholds for IS/OOS generation will be configurable in NR.

While the RLM functionality had significant changes in NR (i.e., a moreconfigurable procedure has been defined in which the network can definethe RS type, exact resources to be monitored, and even the BLER for ISand OOS indications), RLF did not have major changes in NR compared toLTE. In RAN2 #99-bis in Prague, it was agreed that (1) RLF detectionwill be specified for NR in the RRC specification (as in LTE) and (2)for December 17, RLF will be based on the periodic IS/OOS indicationsfrom L1 (i.e., this is the same frame work as LTE). Moreover, it wasagreed that for connected mode, the UE declares RLF upon timer expirydue to DL OOS detection, random access procedure failure detection, andRLC failure detection. It is for further study (FFS) whether maximumAutomatic Repeat Request (ARQ) retransmission is the only criteria forradio link control (RLC) failure. It was also agreed that in the NR RLMprocedure, the physical layer performs OOS/IS indication and RRCdeclares RLF. It was also agreed that for RLF purposes, the RAN 2preference is that the IS/OOS indication should be a per-cellindication, with an aim for a single procedure for both multi-beam andsingle-beam operation.

At RAN2 #99 in Berlin, it was further agreed that the RAN2 understandingof RAN 1 agreements that at least physical layer informs RRC of periodicOOS/IS indications, and that the baseline behavior when there are noindications from the lower layers related to beam failure/recovery isthat (1) RRC detects a DL radio link problem if consecutive N1 number ofperiodic OOS indications are received and (2) RRC stops the timer ifconsecutive N2 number of periodic IS indications are received while thetimer runs. In other words, as in LTE, one can assume that RLF in NRwill also be governed by the following parameter or equivalent ones:counters N310, N311, N313, N314; and timers 310, T311, T301, T313, T314.

How the RLF variables could be configured in NR and UE behavior asrecently agreed for NR is reproduced below.

5.3.11 Radio link failure related actions 5.3.11.1 Detection of physicallayer problems in RRC_CONNECTED The UE shall: 1> upon receiving N310consecutive “out-of-sync” indications for the PCell from lower layerswhile T311 is not running: 2> start timer T310; 1> upon receiving N313consecutive “out-of-sync” indications for the PSCell from lower layerswhile T307 is not running: 2> start T313; FFS: Under which conditionphysical layer problems detection is performed, e.g. neither T300, T301,T304 nor T311 is running. It's subject to the harmonization of the RRCprocedures for RRC Connection establishment/resume/ re-establishment andRRC connection reconfiguration. FFS: The naming of the timers. 5.3.11.2Recovery of physical layer problems Upon receiving N311 consecutive“in-sync” indications for the PCell from lower layers while T310 isrunning, the UE shall: 1> stop timer T310; FFS: whether to support T312for early RLF declaration in NR. NOTE 1: In this case, the UE maintainsthe RRC connection without explicit signalling, i.e. the UE maintainsthe entire radio resource configuration. NOTE 2: Periods in time whereneither “in-sync” nor “out- of-sync” is reported by layer 1 do notaffect the evaluation of the number of consecutive “in-sync” or“out-of-sync” indications. Upon receiving N314 consecutive “in-sync”indications for the PSCell from lower layers while T313 is running, theUE shall: 1> stop timer T313; 5.3.11.3 Detection of radio link failureThe UE shall: 1> upon T310 expiry; or 1> upon random access problemindication from MCG MAC while T311 is not running; or FFS: Under whichcondition physical layer problems detection is performed, e.g. neitherT300, T301, T304 nor T311 is running. It's subject to the harmonizationof the RRC procedures for RRC Connection establishment/resume/re-establishment and RRC connection reconfiguration. 1> upon indicationfrom MCG RLC that the maximum number of retransmissions has been reachedfor an SRB or for an MCG or split DRB: FFS whether maximum ARQretransmission is on1y criteria for RLC failure. 2> consider radio linkfailure to be detected for the MCG i.e. RLF; FFS Whether indicationsrelated to beam failure recovery may affect the declaration of RLF. FFS:How to handle RLC failure in CA duplication for MCG DRB and SRB. FFS:RLF related measurement reports e.g VarRLF-Report is supported in NR. 2>if AS security has not been activated: 3> perform the actions uponleaving RRC_CONNECTED as specified in x.x.x, with release cause ‘other’;2> else: 3> initiate the connection re-establishment procedure asspecified in x.x.x; The UE shall: 1> upon T313 expiry; or 1> upon randomaccess problem indication from SCG MAC; or 1> upon indication from SCGRLC that the maximum number of retransmissions has been reached for anSCG SRB, SCG or split DRB: 2> consider radio link failure to be detectedfor the SCG i.e. SCG-RLF; FFS: How to handle RLC failure in CAduplication for SCG DRB and SRB. 2> initiate the SCG failure informationprocedure as specified in 5.6.4 to report SCG radio link failure;

Additional information about the timers and constants could beconfigured in NR are provided in Tables 4 and 5 below, respectively.

TABLE 4 Timers Timer Start Stop At expiry T307 Reception of Successfulcompletion of random Inform E- RRCConnectionReconfiguration access onthe PSCell, upon initiating UTRAN/NR about the message includingre-establishment and upon SCG release SCG change failureMobilityControlInfoSCG by initiating the SCG failure informationprocedure as specified in 5.6.4. T310 Upon detecting physical layer Uponreceiving N311 consecutive in- If security is not problems for the PCelli.e. sync indications from lower layers for activated: go to uponreceiving N310 consecutive the PCell, upon triggering the RRC_IDLE else:out-of-sync indications from handover procedure and upon initiatinginitiate the connection lower layers the connection re-establishmentre-establishment procedure procedure T311 Upon initiating the RRCSelection of a suitable NR cell or a Enter RRC_IDLE connectionre-establishment cell using another RAT. procedure T313 Upon detectingphysical layer Upon receiving N314 consecutive in- Inform E- problemsfor the PSCell i.e. sync indications from lower layers for UTRAN/NRabout the upon receiving N313 consecutive the PSCell, upon initiatingthe SCG radio link failure out-of-sync indications from connectionre-establishment procedure, by initiating the SCG lower layers upon SCGrelease and upon receiving failure informationRRCConnectionReconfiguration including procedure as specifiedMobilityControlInfoSCG in 5.6.4.

TABLE 5 Constants Constant Usage N310 Maximum number of consecutive“out-of-sync” indications for the PCell received from lower layers N311Maximum number of consecutive “in-sync” indications for the PCellreceived from lower layers N313 Maximum number of consecutive“out-of-sync” indications for the PSCell received from lower layers N314Maximum number of consecutive “in-sync” indications for the PSCellreceived from lower layers

As noted above, the IE RLF-TimersAndConstants contains UE specifictimers and constants applicable for UEs in RRC_CONNECTED. An example ofhow the ASN.1 for the RLF-TimersAndConstants IE could appear in NR isshown below.

-- ASN1START RLF-TimersAndConstants::= CHOICE {  release   NULL,  setup  SEQUENCE {   t301   ENUMERATED {    ms100, ms200, ms300, ms400, ms600,ms1000, ms1500,    ms2000, ms2500, ms3000, ms3500, ms4000, ms5000,   ms6000,  ms8000, ms10000},   t310   ENUMERATED {    ms0, ms50, ms100,ms200, ms500, ms1000, ms2000, ms4000, ms6000},   n310   ENUMERATED {n20},    n1, n2, n3, n4, n6, n8, n10,   t311   ENUMERATED {   ms1000,  ms3000, ms5000, ms10000, ms15000,    ms20000, ms30000},  n311   ENUMERATED {    n1, n2, n3, n4, n5, n6, n8, n10},   ...  } }  t313  ENUMERATED {   ms0, ms50, ms100, ms200, ms500, ms1000, ms2000},  n313  ENUMERATED {   n1, n2, n3, n4, n6, n8, n10, n20},   n314 ENUMERATED {   n1, n2, n3, n4, n5, n6, n8, n10},   ...  } } -- ASN1STOP

RAN1 introduced the concept of bandwidth parts (BWPs), which intends toconfigure the UE with an operation bandwidth that can be less than theactual carrier bandwidth. This has similarities to the handling of“bandwidth reduced” UEs in LTE (Cat-M1), which are not able to operateon the entire carrier bandwidth. Note that this description is primarilyabout carriers spanning several 100 MHz and UEs supporting, for example,“only” carriers of 100 MHz. In other words, this concept addresses UEssupporting an operating bandwidth that is 100 times wider than forCat-M1. Like in LTE Cat-M1, the configured BWP may not coincide with thecarrier's SSB (PSS/SSS/PBCH/Master Information Block (MIB)) and it mustbe determined how the UE acquires cell synchronization, performsmeasurements, and acquires system information block (SIB) in such cases.Besides this core part of the BWP functionality, RAN1 also discussedother variations (e.g., with additional SSBs in the same carrier or inthe same BWP as well as the possibility to configure a UE with severalpossibly overlapping BWPs among which the network can switch by means ofL1 control signals (e.g., downlink control information (DCI)).

FIG. 3 illustrates an example of bandwidth parts. More particularly,FIG. 3 illustrates the bandwidth of a single wide component carrier 300made up of a number of physical resource blocks (PRBs) 1 through N. Inthe example of FIG. 3, three BWPs are shown, BWPs 305A, 305B, and 305C.BWP 305A is a first bandwidth part for a first UE, UE 1. BWP 305B is afirst bandwidth part for a second UE, UE2. BWP 305C is a secondbandwidth part for the second UE, UE2. BWP 305A for UE1 corresponds tothe max bandwidth of UE1, while BWP 305C corresponds to the maxbandwidth of UE2.

The DL and UL BWPs determine the frequency range in which the UE isrequired to receive and transmit data channels (e.g., Physical DL SharedChannel (PDSCH) and Physical UL Shared Channel (PUSCH)) andcorresponding control channels (PDCCH and Physical UL Control Channel(PUCCH)). As a starting point, a BWP cannot span more than theconfigured carrier bandwidth. Thus, a BWP is smaller or equal to (butnot larger than) than the carrier bandwidth.

A key aspect of the BWP concept (as opposed to using only the carrierbandwidth) is to support UEs that cannot handle the entire carrierbandwidth. UEs supporting the full carrier bandwidth can also utilizethe entire carrier. Hence, it is envisioned that the network configuresthe DL BWP and the UL BWP in dedicated signaling in accordance with theUE capabilities.

For example, BWPs can be configured by dedicated signaling in the firstRRCConnectionReconfiguration after connection establishment (i.e., whenthe network knows the UE capabilities). Before that point in time,however, the UE must read the PDCCH and PDSCH to acquire SIB1 to receivepaging messages and to receive Msg2, Msg4 (of the random accessprocedure) and the above-described RRCConnectionReconfiguration. Hence,the UE must be configured with an “initial BWP.” In RAN 1, it was agreedthat there is an initial active DL/UL BWP pair that is valid for a UEuntil the UE is explicitly configured (or reconfigured) with BWP(s)during or after RRC connection is established. It was further agreedthat the initial active DL/UL bandwidth part is confined within the UEminimum bandwidth for the given frequency band. The details of initialactive DL/UL BWP are for further study.

In some cases, a network may decide to configure a wider initial BWPthan some UEs support. This may be the case, for example, if the networkwants to optimize the SIB acquisition time or connection establishmenttime by using a wider bandwidth. But this situation may also occur if alegacy network does not yet support UEs with lower complexity. The UEdiscovers this based on the initial BWP configured in MIB and, since itcannot acquire SIB1, it should consider the cell as barred.

Upon successful connection establishment, the network should configure aBWP in accordance with the UE capabilities. The BWP configuration isspecific for a serving cell (i.e., the network must configure at least aDL BWP for each serving cell). The UL BWP is configured for PrimaryCells (PCells) and for Secondary Cells (SCells) with configured UL.

FIG. 4 illustrates an example of default bandwidth parts. Moreparticularly, FIG. 4 illustrates the bandwidth of a single widecomponent carrier 400 made up of a number of PRBs 1 through N. Inaddition, component carrier 400 also includes an SSB. In the example ofFIG. 4, four BWPs are shown, BWPs 405A, 405B, 405C, and 405D. BWP 405Ais a first bandwidth part, while BWP 405B is the default bandwidth partfor BWP 405A. Similarly, BWP 405C is a second bandwidth part, while BWP405D is the default BWP for BWP 405C.

In LTE, each cell was characterized by its center frequency (UL+DL forFrequency Division Duplex (FDD)), by the carrier bandwidth, and by thePCI conveyed in PSS/SSS. The PSS/SSS used to be at the carrier's centerfrequency. In NR, however, the SSB-frequency is not necessarily thecenter frequency, which will require signaling both values or one valueand an offset (as already discussed in the context of Radio ResourceManagement (RRM) measurements). Upon initial access, the UE mustdiscover the (one) SSB, acquire synchronization, acquire MIB, and thenattempt to read SIB 1. At this point the UE has selected the cell (i.e.,an SSB on a certain frequency).

When the UE establishes an RRC connection, the network may configure adedicated BWP. That BWP may overlap with the SSB's frequency. If so, theUE is able to acquire (or re-acquire) the SSB at any time in order tore-gain sync and to perform SS-based measurements. If the UE's DL BWPcoincides with the SSB-frequency of the UE's serving cell, the UE doesnot require inter-frequency measurement gaps to acquire (or re-acquire)the SSB and to perform SS-based measurements.

If the operating bandwidth of a cell (carrier) is wide and if many UEshave an operation bandwidth that is significantly narrower than thecarrier bandwidth, however, the network will allocate UEs to BWPs thatdo not coincide with the SSB frequency in order to balance the load andto maximize the system capacity. Such a scenario is illustrated in FIG.4, where BWP 405A and 405C do not coincide with the SSB on componentcarrier 400. As in LTE Cat-M1, this implies that these UEs need(inter-frequency, intra-carrier) measurement gaps to re-sync with theirserving cell's SSB and to detect and measure neighbor cells. In otherwords, if the UE's DL BWP does not coincide with the SSB-frequency ofthe UE's serving cell, the UE requires inter-frequency (intra-carrier)measurement gaps to acquire (or re-acquire) the SSB and to performSS-based measurements.

This is a natural consequence of the decision to deploy a cell with awide operating bandwidth with just a single SSB and a single occurrenceof System Information. Nevertheless, RAN1 suggests introducing thepossibility to inform a UE about additional SSB frequencies within acarrier and thereby ensure that each/more UE find an SSB in theirconfigured BWP. At first glance this would remove the need formeasurement gaps. It does not, however, fit with how RAN2 defined RRMmeasurements. In most RRM measurement events, the UE compares a neighborcell to the serving cell. As explained above, a cell is characterized byan SSB on a certain frequency and by the associated SIB1. The UE selectssuch cell (initial access) or is configured with that serving cell(e.g., during handover (HO) SCell addition). This seems to suggest thata UE being configured with a BWP containing its own SSB should be movedto that cell (i.e., the UE must do an inter-frequency HO from itsoriginal serving cell's SSB to the BWP's SSB). If that SSB is alsoassociated with system information (at least SIB1), the UE can camp onthat SSB, which is actually just another cell. Thus, configuring a UEwith a BWP and an SSB inside that BWP is equivalent to aninter-frequency HO if that SSB is associated with at least SIB1.

This ensures that all RRM measurement definitions remain unchanged(i.e., the UE considers simply that new SSB as its serving cell andsearches (typically) for neighbor cells' SSBs on the same frequency).

A change of the BWP will typically require re-tuning the UE's radiofrequency (RF). Such RF re-tuning occurs, for example, upon SCellActivation/Deactivation in LTE. Based on the RAN4 assessment, it causedat least interruptions (e.g., glitches) in the order of a subframe.Activating a new carrier was found to take up to ˜30 ms. RAN4 has notinvestigated how long it may take to switch among BWPs. It may depend onwhether the BWPs use the same SSB as synchronization reference and onwhether one BWP is just a subset of the other BWP or not. RAN1 discussedthe possibility to configure several possibly overlapping BWPs via RRCand to toggle then more dynamically by L1 control signaling.

The topic of BWP and multi-SSB per carrier was discussed in RAN2 #99-bisand the following agreements were made for BWP operation in CONNECTEDmode. RRC signaling supports to configure one or more BWPs (both for DLBWP and UL BWP) for a serving cell (PCell, PSCell). RRC signalingsupports to configure 0, 1 or more BWPs (both for DL BWP and UL BWP) fora serving cell SCell (at least 1 DL BWP). For a UE, the PCell, PSCelland each SCell has a single associated SSB in frequency (the RAN1terminology is the “cell defining SSB”). Cell defining SS block can bechanged by synchronous reconfiguration for PCell/PSCell and SCellrelease/add for the SCell. Each SS block frequency which needs to bemeasured by the UE should be configured as an individual measurementobject (i.e., one measurement object corresponds to a single SS blockfrequency). The cell defining SS block is considered as the timereference of the serving cell, and for RRM serving cell measurementsbased on SSB (irrespective of which BWP is activated). Whether furtheroptimisation is needed for change of SS block location in frequency (butwith no change to PCI and no change in system frame number (SFN)) to bechanged by RRC reconfiguration of physical layer parameters with no L2involvement is for further study.

Considering that RLM can be performed by configuring PBCH/SS blocks orCSI-RS resources, and that for a given cell there will be only onePBCH/SS Block and that might not fall within the active BWP, there aresome problems for RLM configuration in the context of BWPs. The mainproblem is that when changing BWP (e.g., using L1 signaling or relyingon a timer-based solution where the UE should switch from one BWP toanother BWP when the timer expires), the UE may require usingmeasurement gaps to perform RRM measurements even for the serving cellin the case these are configured to be based on PBCH/SS blocks and thePBCH/SS block for the serving cell is not within the active BWP the UEis being switched to. In addition, changing BWP may lead to changes inthe RLM resources the UE monitors, especially if the PDCCH configurationalso changes. Furthermore, there could be a need to change the RS typethe UE monitors as the target active BWP may not include the RStype/resources the UE was monitoring in the previous active BWP. Theremay also be a change in the number of RLM resources.

SUMMARY

To address the foregoing problems with existing solutions, disclosed isa method in a UE. The method comprises obtaining one or more radio linkmonitoring configurations, each radio link monitoring configurationassociated with at least one bandwidth part. The method comprisesdetermining that the UE is to switch from a source bandwidth part to atarget bandwidth part. The method comprises performing radio linkmonitoring on the target bandwidth part according to an obtained radiolink monitoring configuration associated with the target bandwidth part.

In certain embodiments, obtaining the one or more radio link monitoringconfigurations may comprise receiving the one or more radio linkmonitoring configurations in a message from a network node. In certainembodiments, obtaining the one or more radio link monitoringconfigurations may comprise determining the one or more radio linkmonitoring configurations according to one or more pre-defined rules.

In certain embodiments, each radio link monitoring configuration maycomprise: a set of radio resources for performing radio link monitoringwithin its associated bandwidth part; and one or more configurationparameters for performing radio link monitoring within its associatedbandwidth part.

In certain embodiments, the set of radio resources may comprise a CSI-RSresource. In certain embodiments, the set of radio resources maycomprise a SSB.

In certain embodiments, the one or more configuration parameters forperforming radio link monitoring within its associated bandwidth partmay comprise one or more of: one or more filtering parameters; one ormore radio link failure timers; an evaluation period; a number ofretransmissions before radio link failure is declared; a hypotheticalchannel configuration; a hypothetical signal configuration; and amapping function for a measured link quality and a hypothetical channelblock error rate. In certain embodiments, the one or more configurationparameters for performing radio link monitoring within its associatedbandwidth part may comprise one or more filtering parameters and the oneor more filtering parameters may comprise one or more of N310, N311, andN313, N314 counters. In certain embodiments, the one or moreconfiguration parameters for performing radio link monitoring within itsassociated bandwidth part may comprise one or more radio link failuretimers and the one or more radio link failure timers may comprise one ormore of T310, T311, T313, and T314 timers.

In certain embodiments, at least one of the obtained one or more radiolink monitoring configurations may comprise a default radio linkmonitoring configuration. In certain embodiments, the default radio linkmonitoring configuration may be associated with a default bandwidthpart.

In certain embodiments, the method may comprise performing monitoring ofa downlink channel quality of a first bandwidth part and a secondbandwidth part. In certain embodiments, the performing monitoring maycomprise: estimating, during a first period of time, a radio linkquality of the first bandwidth part according to a radio link monitoringconfiguration associated with the first bandwidth part; and estimating,during a second period of time, a radio link quality of the secondbandwidth part according to a radio link monitoring configurationassociated with the second bandwidth part, wherein the second period oftime at least partially overlaps with the first period of time. Incertain embodiments, the first bandwidth part may comprise the sourcebandwidth part and the second bandwidth part may comprise the targetbandwidth part. In certain embodiments, the monitoring may be triggeredbased on an activation rate of one or more of the first bandwidth partand the second bandwidth part.

In certain embodiments, the radio link monitoring configurationassociated with the target bandwidth part may comprise a plurality ofsets of radio resources, and the method may further comprise selectingone or more of the plurality of sets of radio resources to use toperform radio link monitoring on the target bandwidth part based on apre-defined rule.

In certain embodiments, a plurality of radio link monitoringconfigurations may be associated with the target bandwidth part, and themethod may further comprise receiving an instruction via downlinkcontrol information to use one of the plurality of radio link monitoringconfigurations to perform radio link monitoring on the target bandwidthpart.

In certain embodiments, a radio link monitoring configuration associatedwith the source bandwidth part and the radio link monitoringconfiguration associated with the target bandwidth part may use the sameradio resources, and performing radio link monitoring on the targetbandwidth part according to the obtained radio link monitoringconfiguration associated with the target bandwidth part may compriseusing one or more of previously-performed measurements andpreviously-performed measurement samples to generate out-of-sync andin-sync events.

In certain embodiments, a radio link monitoring configuration associatedwith the source bandwidth part and the radio link monitoringconfiguration associated with the target bandwidth part may usedifferent radio resources. In certain embodiments, performing radio linkmonitoring on the target bandwidth part according to the obtained radiolink monitoring configuration associated with the target bandwidth partmay comprise applying a relation function to one or more ofpreviously-performed measurements and previously-performed measurementsamples to generate out-of-sync and in-sync events without resetting aradio link failure timer or a radio link failure counter. In certainembodiments, performing radio link monitoring on the target bandwidthpart according to the obtained radio link monitoring configurationassociated with the target bandwidth part may comprise resetting atleast one of a radio link failure timer and a radio link failurecounter. In certain embodiments, resetting at least one of a radio linkfailure timer and a radio link failure counter may comprise resetting aset of radio link failure timers and radio link failure countersassociated with radio link monitoring for out-of-synch events andallowing a set of radio link failure timers and radio link failurecounters associated with radio link monitoring for in-synch events tocontinue. In certain embodiments, resetting at least one of a radio linkfailure timer and a radio link failure counter may comprise resettingone or more radio link failure timers without resetting any radio linkfailure counters.

Also disclosed is a UE. The UE comprises a receiver, a transmitter, andprocessing circuitry coupled to the receiver and the transmitter. Theprocessing circuitry is configured to obtain one or more radio linkmonitoring configurations, each radio link monitoring configurationassociated with at least one bandwidth part. The processing circuitry isconfigured determine that the UE is to switch from a source bandwidthpart to a target bandwidth part. The processing circuitry is configuredto perform radio link monitoring on the target bandwidth part accordingto an obtained radio link monitoring configuration associated with thetarget bandwidth part.

Also disclosed is a computer program, the computer program comprisinginstructions configured to perform the above-described method in a UE.

Also disclosed is a computer program product, the computer programproduct comprising a non-transitory computer-readable storage medium,the non-transitory computer-readable storage medium comprising acomputer program comprising computer-executable instructions which, whenexecuted on a processor, are configured to perform the above-describedmethod in a UE.

Also disclosed is a method in a network node. The method comprisesdetermining one or more radio link monitoring configurations, each radiolink monitoring configuration associated with at least one bandwidthpart. The method comprises configuring a UE to perform radio linkmonitoring on a target bandwidth part according to a radio linkmonitoring configuration associated with the target bandwidth part.

In certain embodiments, configuring the UE to perform radio linkmonitoring on the target bandwidth part according to the radio linkmonitoring configuration associated with the target bandwidth part maycomprise sending an indication of the radio link monitoringconfiguration associated with the target bandwidth part to the UE. Incertain embodiments, sending the indication of the radio link monitoringconfiguration associated with the target bandwidth part to the UE maycomprise sending an indication of the radio link monitoringconfiguration associated with the target bandwidth part in aninformation element within a bandwidth part configuration for the targetbandwidth part. In certain embodiments, sending the indication of theradio link monitoring configuration associated with the target bandwidthpart to the UE may comprise sending an indication of the radio linkmonitoring configuration associated with the target bandwidth part in aninformation element within a serving cell configuration. In certainembodiments, the indication may comprise a radio link monitoringconfiguration identifier.

In certain embodiments, configuring the UE to perform radio linkmonitoring on the target bandwidth part according to the radio linkmonitoring configuration associated with the target bandwidth part maycomprise configuring the UE to determine the radio link monitoringconfiguration associated with the target bandwidth part according to oneor more predefined rules.

In certain embodiments, each radio link monitoring configuration maycomprise a set of radio resources for performing radio link monitoringwithin its associated bandwidth part and one or more configurationparameters for performing radio link monitoring within its associatedbandwidth part. In certain embodiments, the set of radio resources maycomprise a CSI-RS resource. In certain embodiments, the set of radioresources may comprise a SSB.

In certain embodiments, the one or more configuration parameters forperforming radio link monitoring within its associated bandwidth partcomprise one or more of: one or more filtering parameters; one or moreradio link failure timers; an evaluation period; a number ofretransmissions before radio link failure is declared; a hypotheticalchannel configuration; a hypothetical signal configuration; and amapping function for a measured link quality and a hypothetical channelblock error rate. In certain embodiments, the one or more configurationparameters for performing radio link monitoring within its associatedbandwidth part may comprise one or more filtering parameters and the oneor more filtering parameters may comprise one or more of N310, N311, andN313, N314 counters. In certain embodiments, the one or moreconfiguration parameters for performing radio link monitoring within itsassociated bandwidth part may comprise one or more radio link failuretimers and the one or more radio link failure timers may comprise one ormore of T310, T311, T313, and T314 timers.

In certain embodiments, at least one of the determined one or more radiolink monitoring configurations may comprise a default radio linkmonitoring configuration. In certain embodiments, the default radio linkmonitoring configuration may be associated with a default bandwidthpart.

In certain embodiments, the radio link monitoring configurationassociated with the target bandwidth part may comprise a plurality ofsets of radio resources, and the method may further comprise configuringthe UE to select one or more of the plurality of sets of radio resourcesto use to perform radio link monitoring on the target bandwidth partbased on a pre-defined rule.

In certain embodiments, a plurality of radio link monitoringconfigurations may be associated with the target bandwidth part, and themethod may further comprise sending an instruction to the UE to use oneof the plurality of radio link monitoring configurations to performradio link monitoring on the target bandwidth part.

In certain embodiments, a radio link monitoring configuration associatedwith a source bandwidth part and the radio link monitoring configurationassociated with the target bandwidth part may use the same radioresources, and configuring the UE to perform radio link monitoring onthe target bandwidth part according to the radio link monitoringconfiguration associated with the target bandwidth part may compriseconfiguring the UE to use one or more of previously-performedmeasurements and previously-performed measurement samples to generateout-of-sync and in-sync events.

In certain embodiments, a radio link monitoring configuration associatedwith a source bandwidth part and the radio link monitoring configurationassociated with the target bandwidth part may use different radioresources. In certain embodiments, configuring the UE to perform radiolink monitoring on the target bandwidth part according to the radio linkmonitoring configuration associated with the target bandwidth part maycomprise configuring the UE to apply a relation function to one or morepreviously-performed measurements and previously-performed measurementsamples to generate out-of-sync and in-sync events without resetting aradio link failure timer or a radio link failure counter. In certainembodiments, configuring the UE to perform radio link monitoring on thetarget bandwidth part according to the radio link monitoringconfiguration associated with the target bandwidth part may compriseconfiguring the UE to reset at least one of a radio link failure timerand a radio link failure counter. In certain embodiments, configuringthe UE to reset at least one of a radio link failure timer and a radiolink failure counter may comprise configuring the UE to reset a set ofradio link failure timers and radio link failure counters associatedwith radio link monitoring for out-of-synch events and configuring theUE to allow a set of radio link failure timers and radio link failurecounters associated with radio link monitoring for in-synch measurementsto continue. In certain embodiments, configuring the UE to reset atleast one of a radio link failure timer and a radio link failure countermay comprise configuring the UE to reset one or more radio link failuretimers without resetting any radio link failure counters.

Also disclosed is a network node. The network node comprises a receiver,a transmitter, and processing circuitry coupled to the receiver and thetransmitter. The processing circuitry is configured to determine one ormore radio link monitoring configurations, each radio link monitoringconfiguration associated with at least one bandwidth part. Theprocessing circuitry is configured to configure a UE to perform radiolink monitoring on a target bandwidth part according to a radio linkmonitoring configuration associated with the target bandwidth part.

Also disclosed is a computer program, the computer program comprisinginstructions configured to perform the above-described method in anetwork node.

Also disclosed is a computer program product, the computer programproduct comprising a non-transitory computer-readable storage medium,the non-transitory computer-readable storage medium comprising acomputer program comprising computer-executable instructions which, whenexecuted on a processor, are configured to perform the above-describedmethod in a network node.

Certain embodiments of the present disclosure may provide one or moretechnical advantages. For example, certain embodiments mayadvantageously enable an efficient change in radio link monitoring/radiolink failure configuration when the UE changes bandwidth part. This mayadvantageously allow frequent measurement gaps to be avoided withoutexcessive additional signaling. Other advantages may be readily apparentto one having skill in the art. Certain embodiments may have none, some,or all of the recited advantages.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the disclosed embodiments and theirfeatures and advantages, reference is now made to the followingdescription, taken in conjunction with the accompanying drawings, inwhich:

FIG. 1 illustrates an example of how PDCCH can be scheduled over thewhole DL transmission bandwidth;

FIG. 2 illustrates an example procedure for evaluating RLF;

FIG. 3 illustrates an example of bandwidth parts;

FIG. 4 illustrates an example of default bandwidth parts;

FIGS. 5A and 5B illustrate a wideband component carrier with a singleSSB frequency location and multiple bandwidth parts;

FIG. 6 illustrates an example wireless communications network, inaccordance with certain embodiments;

FIG. 7 is a flowchart of a method in a UE, in accordance with certainembodiments;

FIG. 8 is a schematic block diagram of a virtualization apparatus, inaccordance with certain embodiments;

FIG. 9 is a flowchart of a method in a network node, in accordance withcertain embodiments;

FIG. 10 is a schematic block diagram of a virtualization apparatus, inaccordance with certain embodiments;

FIG. 11 illustrates one embodiment of a UE, in accordance with certainembodiments;

FIG. 12 is a schematic block diagram illustrating a virtualizationenvironment, in accordance with certain embodiments;

FIG. 13 illustrates an example telecommunication network connected viaan intermediate network to a host computer, in accordance with certainembodiments;

FIG. 14 illustrates an example of a host computer communicating via abase station with a UE over a partially wireless connection, inaccordance with certain embodiments;

FIG. 15 is a flowchart of a method implemented in a communicationsystem, in accordance with certain embodiments;

FIG. 16 is a flowchart of a method implemented in a communicationsystem, in accordance with certain embodiments;

FIG. 17 is a flowchart of a method implemented in a communicationsystem, in accordance with certain embodiments; and

FIG. 18 is a flowchart of a method implemented in a communicationsystem, in accordance with certain embodiments.

DETAILED DESCRIPTION

Generally, all terms used herein are to be interpreted according totheir ordinary meaning in the relevant technical field, unless adifferent meaning is clearly given and/or is implied from the context inwhich it is used. All references to a/an/the element, apparatus,component, means, step, etc. are to be interpreted openly as referringto at least one instance of the element, apparatus, component, means,step, etc., unless explicitly stated otherwise. The steps of any methodsdisclosed herein do not have to be performed in the exact orderdisclosed, unless a step is explicitly described as following orpreceding another step and/or where it is implicit that a step mustfollow or precede another step. Any feature of any of the embodimentsdisclosed herein may be applied to any other embodiment, whereverappropriate. Likewise, any advantage of any of the embodiments may applyto any other embodiments, and vice versa. Other objectives, features andadvantages of the enclosed embodiments will be apparent from thefollowing description.

As described above, in NR RLM can be performed by configuring PBCH/SSBlocks or CSI-RS resources, and for a given cell there will be only onePBCH/SS Block (which might not fall within the active BWP). As a result,there are certain problems for RLM configuration that may occur in thecontext of BWPs. For example, when changing BWP, the UE may need to usemeasurement gaps to perform RRM measurements even for the serving cellin cases where RRM measurements are configured to be based on PBCH/SSBlocks and the PBCH/SS Block for the serving cell is not within theactive BWP the UE is switching to.

For RRM measurements on the serving cell, measurement gaps could be usedas in LTE Cat-M1 UEs. RLM measurements used to compute the SINR (to thenmap to a Qout/Qin threshold relative to a mapped BLER so that IS/OOSevents can be generated), however, should be performed much more oftenthan RRM measurements (in LTE on the order of 4 times as often). Inother words, while RRM measurements are typically performed every 40 ms,RLM measurements are performed per radio frame (i.e., every 10 ms). Thatwould mean using extremely frequent measurement gaps (for example inconfigurations where the RS type and/or frequency resources to bemonitored for RLM are outside the active BWP), which is not viable. Theimpact that the placement of the PBCH/SS Block can have on the need formeasurement gaps is illustrated in FIGS. 5A and 5B, which are describedin more detail below.

FIGS. 5A and 5B illustrate a wideband component carrier with a singleSSB frequency location and multiple BWPs. In FIG. 5A, three BWPs 505A,505B, and 505C are illustrated. Additionally, there is a single SSB510A. As can be seen from FIG. 5A, SSB 510A falls within each of BWPs505A, 505B, and 505C. Thus, when switching between BWPs 505A, 505B, and505C (for example via L1 signaling), there is no need to re-configureRRM measurements when switching BWPs. Thus, there is no need for gaps inthe scenario illustrated in FIG. 5A.

FIG. 5B, meanwhile, illustrates three BWPs 505D, 505E, and 505F. FIG. 5Balso depicts a single SSB 510B. In contrast to the scenario illustratedin FIG. 5A, in FIG. 5B only one of the BWPs, BWP 505E, includes SSB510B. Thus, when switching between BWPs (for example via L1 signaling),if the active BWP is re-configured to be BWP 505D or BWP 505F, a UE mayneed gaps (i.e., reconfiguration upon BWP switching is needed or atleast the UE should start to use gaps previously configured (activationof a previously configured gap)). For RLM, this would occur toofrequently and would not be not very efficient, especially if SSB 510Bis used for RLM.

In addition to needing to use measurement gaps to perform RRMmeasurements as described above, there are other problems for RLMconfiguration that may occur in the context of BWPs. As an additionalexample, changing BWP may lead to changes in the RLM resources the UEmonitors (especially if the PDCCH configuration also changes). Asanother example, there could be a need to change the RS type the UEmonitors, as the target active BWP may not include the RS type/resourcesthe UE was monitoring in the previous active BWP. As yet anotherexample, there may also be a change in the number of RLM resources.

A possible alternative could be to rely on RRC signaling (e.g., RRCConnection Reconfiguration) for scenarios in which the target BWP tobecome active does not include the resources the UE was monitoring forRLM purposes in the source BWP. That would mean, however, that everytime there is a change from a source BWP to a target BWP (whether donevia L1 signaling or based on the timer RAN1 has agreed to) RRC signalingwill be needed. This defeats the purpose of the signaling optimizationfor BWP switching.

Additionally, the relation (and thus the mapping) between a measuredchannel quality (e.g., SINR) and the hypothetical control channel BLERmay be different depending on the BWP. Furthermore, an old BWP maycontain SS Blocks and thus SS Block-based RLM may be configured, while anew BWP may not contain SS Blocks and therefore CSI-RS-based RLM (whereCSI-RS are contained within the new BWP) may be more useful.

Certain aspects of the present disclosure and the embodiments describedherein may provide solutions to these or other challenges. According toone example embodiment, a method in a wireless device (WD) (e.g., a UE)is disclosed. The WD obtains one or more RLM configurations, each RLMconfiguration associated with at least one BWP. In certain embodiments,the WD may obtain the one or more RLM configurations by receiving theone or more RLM configurations in a message from a network node (e.g., agNB). In certain embodiments, the WD may obtain the one or more RLMconfigurations by determining the one or more RLM configurationsaccording to one or more pre-defined rules. In certain embodiments, eachRLM configuration may comprise a set of radio resources for performingRLM within its associated BWP and one or more configuration parametersfor performing RLM within its associated bandwidth part. The WDdetermines that the WD is to switch from a source BWP to a target BWP.The WD performs RLM on the target BWP according to an obtained RLMconfiguration associated with the target BWP.

According to another example embodiment, a method in a network node(e.g., a gNB) is disclosed. The network node determines one or more RLMconfigurations, each RLM configuration associated with at least one BWP.The network node configures a WD to perform RLM on a target BWPaccording to a RLM configuration associated with the target BWP. Incertain embodiments, the network node may send an indication of the RLMconfiguration associated with the target BWP to the WD (e.g., in an IEwithin a BWP configuration for the target BWP and/or in an IE within aserving cell configuration). In certain embodiments, the indication maycomprise a RLM configuration identifier.

Some of the embodiments contemplated herein will now be described morefully with reference to the accompanying drawings. Other embodiments,however, are contained within the scope of the subject matter disclosedherein, the disclosed subject matter should not be construed as limitedto only the embodiments set forth herein; rather, these embodiments areprovided by way of example to convey the scope of the subject matter tothose skilled in the art.

FIG. 6 illustrates an example wireless communications network, inaccordance with certain embodiments. Although the subject matterdescribed herein may be implemented in any appropriate type of systemusing any suitable components, the embodiments disclosed herein aredescribed in relation to a wireless network, such as the examplewireless network illustrated in FIG. 6. For simplicity, the wirelessnetwork of FIG. 6 only depicts network 106, network nodes 160 and 160 b,and wireless devices (WDs) 110, 110 b, and 110 c. In practice, awireless network may further include any additional elements suitable tosupport communication between wireless devices or between a wirelessdevice and another communication device, such as a landline telephone, aservice provider, or any other network node or end device. Of theillustrated components, network node 160 and WD 110 are depicted withadditional detail. The wireless network may provide communication andother types of services to one or more wireless devices to facilitatethe wireless devices' access to and/or use of the services provided by,or via, the wireless network.

The wireless network may comprise and/or interface with any type ofcommunication, telecommunication, data, cellular, and/or radio networkor other similar type of system. In some embodiments, the wirelessnetwork may be configured to operate according to specific standards orother types of predefined rules or procedures. Thus, particularembodiments of the wireless network may implement communicationstandards, such as Global System for Mobile Communications (GSM),Universal Mobile Telecommunications System (UMTS), Long Term Evolution(LTE), and/or other suitable 2G, 3G, 4G, or 5G standards; wireless localarea network (WLAN) standards, such as the IEEE 802.11 standards; and/orany other appropriate wireless communication standard, such as theWorldwide Interoperability for Microwave Access (WiMax), Bluetooth,Z-Wave and/or ZigBee standards.

Network 106 may comprise one or more backhaul networks, core networks,IP networks, public switched telephone networks (PSTNs), packet datanetworks, optical networks, wide-area networks (WANs), local areanetworks (LANs), wireless local area networks (WLANs), wired networks,wireless networks, metropolitan area networks, and other networks toenable communication between devices.

Network node 160 and WD 110 comprise various components described inmore detail below. These components work together in order to providenetwork node and/or wireless device functionality, such as providingwireless connections in a wireless network. In different embodiments,the wireless network may comprise any number of wired or wirelessnetworks, network nodes, base stations, controllers, wireless devices,relay stations, and/or any other components or systems that mayfacilitate or participate in the communication of data and/or signalswhether via wired or wireless connections.

As used herein, network node refers to equipment capable, configured,arranged and/or operable to communicate directly or indirectly with awireless device and/or with other network nodes or equipment in thewireless network to enable and/or provide wireless access to thewireless device and/or to perform other functions (e.g., administration)in the wireless network. Examples of network nodes include, but are notlimited to, access points (APs) (e.g., radio access points), basestations (BSs) (e.g., radio base stations, Node Bs, evolved Node Bs(eNBs) and NR NodeBs (gNBs)). Base stations may be categorized based onthe amount of coverage they provide (or, stated differently, theirtransmit power level) and may then also be referred to as femto basestations, pico base stations, micro base stations, or macro basestations. A base station may be a relay node or a relay donor nodecontrolling a relay. A network node may also include one or more (orall) parts of a distributed radio base station such as centralizeddigital units and/or remote radio units (RRUs), sometimes referred to asRemote Radio Heads (RRHs). Such remote radio units may or may not beintegrated with an antenna as an antenna integrated radio. Parts of adistributed radio base station may also be referred to as nodes in adistributed antenna system (DAS). Yet further examples of network nodesinclude multi-standard radio (MSR) equipment such as MSR BSs, networkcontrollers such as radio network controllers (RNCs) or base stationcontrollers (BSCs), base transceiver stations (BTSs), transmissionpoints, transmission nodes, multi-cell/multicast coordination entities(MCEs), core network nodes (e.g., MSCs, MMEs), O&M nodes, OSS nodes, SONnodes, positioning nodes (e.g., E-SMLCs), and/or MDTs. As anotherexample, a network node may be a virtual network node as described inmore detail below. More generally, however, network nodes may representany suitable device (or group of devices) capable, configured, arranged,and/or operable to enable and/or provide a wireless device with accessto the wireless network or to provide some service to a wireless devicethat has accessed the wireless network.

In FIG. 6, network node 160 includes processing circuitry 170, devicereadable medium 180, interface 190, auxiliary equipment 184, powersource 186, power circuitry 187, and antenna 162. Although network node160 illustrated in the example wireless network of FIG. 6 may representa device that includes the illustrated combination of hardwarecomponents, other embodiments may comprise network nodes with differentcombinations of components. It is to be understood that a network nodecomprises any suitable combination of hardware and/or software needed toperform the tasks, features, functions and methods disclosed herein.Moreover, while the components of network node 160 are depicted assingle boxes located within a larger box, or nested within multipleboxes, in practice, a network node may comprise multiple differentphysical components that make up a single illustrated component (e.g.,device readable medium 180 may comprise multiple separate hard drives aswell as multiple RAM modules).

Similarly, network node 160 may be composed of multiple physicallyseparate components (e.g., a NodeB component and a RNC component, or aBTS component and a BSC component, etc.), which may each have their ownrespective components. In certain scenarios in which network node 160comprises multiple separate components (e.g., BTS and BSC components),one or more of the separate components may be shared among severalnetwork nodes. For example, a single RNC may control multiple NodeB's.In such a scenario, each unique NodeB and RNC pair, may in someinstances be considered a single separate network node. In someembodiments, network node 160 may be configured to support multipleradio access technologies (RATs). In such embodiments, some componentsmay be duplicated (e.g., separate device readable medium 180 for thedifferent RATs) and some components may be reused (e.g., the sameantenna 162 may be shared by the RATs). Network node 160 may alsoinclude multiple sets of the various illustrated components fordifferent wireless technologies integrated into network node 160, suchas, for example, GSM, WCDMA, LTE, NR, WiFi, or Bluetooth wirelesstechnologies. These wireless technologies may be integrated into thesame or different chip or set of chips and other components withinnetwork node 160.

Processing circuitry 170 is configured to perform any determining,calculating, or similar operations (e.g., certain obtaining operations)described herein as being provided by a network node. These operationsperformed by processing circuitry 170 may include processing informationobtained by processing circuitry 170 by, for example, converting theobtained information into other information, comparing the obtainedinformation or converted information to information stored in thenetwork node, and/or performing one or more operations based on theobtained information or converted information, and as a result of saidprocessing making a determination.

Processing circuitry 170 may comprise a combination of one or more of amicroprocessor, controller, microcontroller, central processing unit,digital signal processor, application-specific integrated circuit, fieldprogrammable gate array, or any other suitable computing device,resource, or combination of hardware, software and/or encoded logicoperable to provide, either alone or in conjunction with other networknode 160 components, such as device readable medium 180, network node160 functionality. For example, processing circuitry 170 may executeinstructions stored in device readable medium 180 or in memory withinprocessing circuitry 170. Such functionality may include providing anyof the various wireless features, functions, or benefits discussedherein. In some embodiments, processing circuitry 170 may include asystem on a chip (SOC).

In some embodiments, processing circuitry 170 may include one or more ofradio frequency (RF) transceiver circuitry 172 and baseband processingcircuitry 174. In some embodiments, radio frequency (RF) transceivercircuitry 172 and baseband processing circuitry 174 may be on separatechips (or sets of chips), boards, or units, such as radio units anddigital units. In alternative embodiments, part or all of RF transceivercircuitry 172 and baseband processing circuitry 174 may be on the samechip or set of chips, boards, or units In certain embodiments, some orall of the functionality described herein as being provided by a networknode, base station, eNB or other such network device may be performed byprocessing circuitry 170 executing instructions stored on devicereadable medium 180 or memory within processing circuitry 170. Inalternative embodiments, some or all of the functionality may beprovided by processing circuitry 170 without executing instructionsstored on a separate or discrete device readable medium, such as in ahard-wired manner. In any of those embodiments, whether executinginstructions stored on a device readable storage medium or not,processing circuitry 170 can be configured to perform the describedfunctionality. The benefits provided by such functionality are notlimited to processing circuitry 170 alone or to other components ofnetwork node 160 but are enjoyed by network node 160 as a whole, and/orby end users and the wireless network generally.

Device readable medium 180 may comprise any form of volatile ornon-volatile computer readable memory including, without limitation,persistent storage, solid-state memory, remotely mounted memory,magnetic media, optical media, random access memory (RAM), read-onlymemory (ROM), mass storage media (for example, a hard disk), removablestorage media (for example, a flash drive, a Compact Disk (CD) or aDigital Video Disk (DVD)), and/or any other volatile or non-volatile,non-transitory device readable and/or computer-executable memory devicesthat store information, data, and/or instructions that may be used byprocessing circuitry 170. Device readable medium 180 may store anysuitable instructions, data or information, including a computerprogram, software, an application including one or more of logic, rules,code, tables, etc. and/or other instructions capable of being executedby processing circuitry 170 and, utilized by network node 160. Devicereadable medium 180 may be used to store any calculations made byprocessing circuitry 170 and/or any data received via interface 190. Insome embodiments, processing circuitry 170 and device readable medium180 may be considered to be integrated.

Interface 190 is used in the wired or wireless communication ofsignalling and/or data between network node 160, network 106, and/or WDs110. As illustrated, interface 190 comprises port(s)/terminal(s) 194 tosend and receive data, for example to and from network 106 over a wiredconnection. Interface 190 also includes radio front end circuitry 192that may be coupled to, or in certain embodiments a part of, antenna162. Radio front end circuitry 192 comprises filters 198 and amplifiers196. Radio front end circuitry 192 may be connected to antenna 162 andprocessing circuitry 170. Radio front end circuitry may be configured tocondition signals communicated between antenna 162 and processingcircuitry 170. Radio front end circuitry 192 may receive digital datathat is to be sent out to other network nodes or WDs via a wirelessconnection. Radio front end circuitry 192 may convert the digital datainto a radio signal having the appropriate channel and bandwidthparameters using a combination of filters 198 and/or amplifiers 196. Theradio signal may then be transmitted via antenna 162. Similarly, whenreceiving data, antenna 162 may collect radio signals which are thenconverted into digital data by radio front end circuitry 192. Thedigital data may be passed to processing circuitry 170. In otherembodiments, the interface may comprise different components and/ordifferent combinations of components.

In certain alternative embodiments, network node 160 may not includeseparate radio front end circuitry 192, instead, processing circuitry170 may comprise radio front end circuitry and may be connected toantenna 162 without separate radio front end circuitry 192. Similarly,in some embodiments, all or some of RF transceiver circuitry 172 may beconsidered a part of interface 190. In still other embodiments,interface 190 may include one or more ports or terminals 194, radiofront end circuitry 192, and RF transceiver circuitry 172, as part of aradio unit (not shown), and interface 190 may communicate with basebandprocessing circuitry 174, which is part of a digital unit (not shown).

Antenna 162 may include one or more antennas, or antenna arrays,configured to send and/or receive wireless signals. Antenna 162 may becoupled to radio front end circuitry 190 and may be any type of antennacapable of transmitting and receiving data and/or signals wirelessly. Insome embodiments, antenna 162 may comprise one or more omni-directional,sector or panel antennas operable to transmit/receive radio signalsbetween, for example, 2 GHz and 66 GHz. An omni-directional antenna maybe used to transmit/receive radio signals in any direction, a sectorantenna may be used to transmit/receive radio signals from deviceswithin a particular area, and a panel antenna may be a line of sightantenna used to transmit/receive radio signals in a relatively straightline. In some instances, the use of more than one antenna may bereferred to as MIMO. In certain embodiments, antenna 162 may be separatefrom network node 160 and may be connectable to network node 160 throughan interface or port.

Antenna 162, interface 190, and/or processing circuitry 170 may beconfigured to perform any receiving operations and/or certain obtainingoperations described herein as being performed by a network node. Anyinformation, data and/or signals may be received from a wireless device,another network node and/or any other network equipment. Similarly,antenna 162, interface 190, and/or processing circuitry 170 may beconfigured to perform any transmitting operations described herein asbeing performed by a network node. Any information, data and/or signalsmay be transmitted to a wireless device, another network node and/or anyother network equipment.

Power circuitry 187 may comprise, or be coupled to, power managementcircuitry and is configured to supply the components of network node 160with power for performing the functionality described herein. Powercircuitry 187 may receive power from power source 186. Power source 186and/or power circuitry 187 may be configured to provide power to thevarious components of network node 160 in a form suitable for therespective components (e.g., at a voltage and current level needed foreach respective component). Power source 186 may either be included in,or external to, power circuitry 187 and/or network node 160. Forexample, network node 160 may be connectable to an external power source(e.g., an electricity outlet) via an input circuitry or interface suchas an electrical cable, whereby the external power source supplies powerto power circuitry 187. As a further example, power source 186 maycomprise a source of power in the form of a battery or battery packwhich is connected to, or integrated in, power circuitry 187. Thebattery may provide backup power should the external power source fail.Other types of power sources, such as photovoltaic devices, may also beused.

Alternative embodiments of network node 160 may include additionalcomponents beyond those shown in FIG. 6 that may be responsible forproviding certain aspects of the network node's functionality, includingany of the functionality described herein and/or any functionalitynecessary to support the subject matter described herein. For example,network node 160 may include user interface equipment to allow input ofinformation into network node 160 and to allow output of informationfrom network node 160. This may allow a user to perform diagnostic,maintenance, repair, and other administrative functions for network node160.

As used herein, wireless device (WD) refers to a device capable,configured, arranged and/or operable to communicate wirelessly withnetwork nodes and/or other wireless devices. Unless otherwise noted, theterm WD may be used interchangeably herein with user equipment (UE).Communicating wirelessly may involve transmitting and/or receivingwireless signals using electromagnetic waves, radio waves, infraredwaves, and/or other types of signals suitable for conveying informationthrough air. In some embodiments, a WD may be configured to transmitand/or receive information without direct human interaction. Forinstance, a WD may be designed to transmit information to a network on apredetermined schedule, when triggered by an internal or external event,or in response to requests from the network. Examples of a WD include,but are not limited to, a smart phone, a mobile phone, a cell phone, avoice over IP (VoIP) phone, a wireless local loop phone, a desktopcomputer, a personal digital assistant (PDA), a wireless cameras, agaming console or device, a music storage device, a playback appliance,a wearable terminal device, a wireless endpoint, a mobile station, atablet, a laptop, a laptop-embedded equipment (LEE), a laptop-mountedequipment (LME), a smart device, a wireless customer-premise equipment(CPE). a vehicle-mounted wireless terminal device, etc. A WD may supportdevice-to-device (D2D) communication, for example by implementing a 3GPPstandard for sidelink communication, vehicle-to-vehicle (V2V),vehicle-to-infrastructure (V2I), vehicle-to-everything (V2X) and may inthis case be referred to as a D2D communication device. As yet anotherspecific example, in an Internet of Things (IoT) scenario, a WD mayrepresent a machine or other device that performs monitoring and/ormeasurements, and transmits the results of such monitoring and/ormeasurements to another WD and/or a network node. The WD may in thiscase be a machine-to-machine (M2M) device, which may in a 3GPP contextbe referred to as an MTC device. As one particular example, the WD maybe a UE implementing the 3GPP narrow band internet of things (NB-IoT)standard. Particular examples of such machines or devices are sensors,metering devices such as power meters, industrial machinery, or home orpersonal appliances (e.g. refrigerators, televisions, etc.) personalwearables (e.g., watches, fitness trackers, etc.). In other scenarios, aWD may represent a vehicle or other equipment that is capable ofmonitoring and/or reporting on its operational status or other functionsassociated with its operation. A WD as described above may represent theendpoint of a wireless connection, in which case the device may bereferred to as a wireless terminal. Furthermore, a WD as described abovemay be mobile, in which case it may also be referred to as a mobiledevice or a mobile terminal.

As illustrated, wireless device 110 includes antenna 111, interface 114,processing circuitry 120, device readable medium 130, user interfaceequipment 132, auxiliary equipment 134, power source 136 and powercircuitry 137. WD 110 may include multiple sets of one or more of theillustrated components for different wireless technologies supported byWD 110, such as, for example, GSM, WCDMA, LTE, NR, WiFi, WiMAX, orBluetooth wireless technologies, just to mention a few. These wirelesstechnologies may be integrated into the same or different chips or setof chips as other components within WD 110.

Antenna 111 may include one or more antennas or antenna arrays,configured to send and/or receive wireless signals, and is connected tointerface 114. In certain alternative embodiments, antenna 111 may beseparate from WD 110 and be connectable to WD 110 through an interfaceor port. Antenna 111, interface 114, and/or processing circuitry 120 maybe configured to perform any receiving or transmitting operationsdescribed herein as being performed by a WD. Any information, dataand/or signals may be received from a network node and/or another WD. Insome embodiments, radio front end circuitry and/or antenna 111 may beconsidered an interface.

As illustrated, interface 114 comprises radio front end circuitry 112and antenna 111. Radio front end circuitry 112 comprise one or morefilters 118 and amplifiers 116. Radio front end circuitry 114 isconnected to antenna 111 and processing circuitry 120, and is configuredto condition signals communicated between antenna 111 and processingcircuitry 120. Radio front end circuitry 112 may be coupled to or a partof antenna 111. In some embodiments, WD 110 may not include separateradio front end circuitry 112; rather, processing circuitry 120 maycomprise radio front end circuitry and may be connected to antenna 111.Similarly, in some embodiments, some or all of RF transceiver circuitry122 may be considered a part of interface 114. Radio front end circuitry112 may receive digital data that is to be sent out to other networknodes or WDs via a wireless connection. Radio front end circuitry 112may convert the digital data into a radio signal having the appropriatechannel and bandwidth parameters using a combination of filters 118and/or amplifiers 116. The radio signal may then be transmitted viaantenna 111. Similarly, when receiving data, antenna 111 may collectradio signals which are then converted into digital data by radio frontend circuitry 112. The digital data may be passed to processingcircuitry 120. In other embodiments, the interface may comprisedifferent components and/or different combinations of components.

Processing circuitry 120 may comprise a combination of one or more of amicroprocessor, controller, microcontroller, central processing unit,digital signal processor, application-specific integrated circuit, fieldprogrammable gate array, or any other suitable computing device,resource, or combination of hardware, software, and/or encoded logicoperable to provide, either alone or in conjunction with other WD 110components, such as device readable medium 130, WD 110 functionality.Such functionality may include providing any of the various wirelessfeatures or benefits discussed herein. For example, processing circuitry120 may execute instructions stored in device readable medium 130 or inmemory within processing circuitry 120 to provide the functionalitydisclosed herein.

As illustrated, processing circuitry 120 includes one or more of RFtransceiver circuitry 122, baseband processing circuitry 124, andapplication processing circuitry 126. In other embodiments, theprocessing circuitry may comprise different components and/or differentcombinations of components. In certain embodiments processing circuitry120 of WD 110 may comprise a SOC. In some embodiments, RF transceivercircuitry 122, baseband processing circuitry 124, and applicationprocessing circuitry 126 may be on separate chips or sets of chips. Inalternative embodiments, part or all of baseband processing circuitry124 and application processing circuitry 126 may be combined into onechip or set of chips, and RF transceiver circuitry 122 may be on aseparate chip or set of chips. In still alternative embodiments, part orall of RF transceiver circuitry 122 and baseband processing circuitry124 may be on the same chip or set of chips, and application processingcircuitry 126 may be on a separate chip or set of chips. In yet otheralternative embodiments, part or all of RF transceiver circuitry 122,baseband processing circuitry 124, and application processing circuitry126 may be combined in the same chip or set of chips. In someembodiments, RF transceiver circuitry 122 may be a part of interface114. RF transceiver circuitry 122 may condition RF signals forprocessing circuitry 120.

In certain embodiments, some or all of the functionality describedherein as being performed by a WD may be provided by processingcircuitry 120 executing instructions stored on device readable medium130, which in certain embodiments may be a computer-readable storagemedium. In alternative embodiments, some or all of the functionality maybe provided by processing circuitry 120 without executing instructionsstored on a separate or discrete device readable storage medium, such asin a hard-wired manner. In any of those particular embodiments, whetherexecuting instructions stored on a device readable storage medium ornot, processing circuitry 120 can be configured to perform the describedfunctionality. The benefits provided by such functionality are notlimited to processing circuitry 120 alone or to other components of WD110, but are enjoyed by WD 110 as a whole, and/or by end users and thewireless network generally.

Processing circuitry 120 may be configured to perform any determining,calculating, or similar operations (e.g., certain obtaining operations)described herein as being performed by a WD. These operations, asperformed by processing circuitry 120, may include processinginformation obtained by processing circuitry 120 by, for example,converting the obtained information into other information, comparingthe obtained information or converted information to information storedby WD 110, and/or performing one or more operations based on theobtained information or converted information, and as a result of saidprocessing making a determination.

Device readable medium 130 may be operable to store a computer program,software, an application including one or more of logic, rules, code,tables, etc. and/or other instructions capable of being executed byprocessing circuitry 120. Device readable medium 130 may includecomputer memory (e.g., Random Access Memory (RAM) or Read Only Memory(ROM)), mass storage media (e.g., a hard disk), removable storage media(e.g., a Compact Disk (CD) or a Digital Video Disk (DVD)), and/or anyother volatile or non-volatile, non-transitory device readable and/orcomputer executable memory devices that store information, data, and/orinstructions that may be used by processing circuitry 120. In someembodiments, processing circuitry 120 and device readable medium 130 maybe considered to be integrated.

User interface equipment 132 may provide components that allow for ahuman user to interact with WD 110. Such interaction may be of manyforms, such as visual, audial, tactile, etc. User interface equipment132 may be operable to produce output to the user and to allow the userto provide input to WD 110. The type of interaction may vary dependingon the type of user interface equipment 132 installed in WD 110. Forexample, if WD 110 is a smart phone, the interaction may be via a touchscreen; if WD 110 is a smart meter, the interaction may be through ascreen that provides usage (e.g., the number of gallons used) or aspeaker that provides an audible alert (e.g., if smoke is detected).User interface equipment 132 may include input interfaces, devices andcircuits, and output interfaces, devices and circuits. User interfaceequipment 132 is configured to allow input of information into WD 110,and is connected to processing circuitry 120 to allow processingcircuitry 120 to process the input information. User interface equipment132 may include, for example, a microphone, a proximity or other sensor,keys/buttons, a touch display, one or more cameras, a USB port, or otherinput circuitry. User interface equipment 132 is also configured toallow output of information from WD 110, and to allow processingcircuitry 120 to output information from WD 110. User interfaceequipment 132 may include, for example, a speaker, a display, vibratingcircuitry, a USB port, a headphone interface, or other output circuitry.Using one or more input and output interfaces, devices, and circuits, ofuser interface equipment 132, WD 110 may communicate with end usersand/or the wireless network, and allow them to benefit from thefunctionality described herein.

Auxiliary equipment 134 is operable to provide more specificfunctionality which may not be generally performed by WDs. This maycomprise specialized sensors for doing measurements for variouspurposes, interfaces for additional types of communication such as wiredcommunications etc. The inclusion and type of components of auxiliaryequipment 134 may vary depending on the embodiment and/or scenario.

Power source 136 may, in some embodiments, be in the form of a batteryor battery pack. Other types of power sources, such as an external powersource (e.g., an electricity outlet), photovoltaic devices or powercells, may also be used. WD 110 may further comprise power circuitry 137for delivering power from power source 136 to the various parts of WD110 which need power from power source 136 to carry out anyfunctionality described or indicated herein. Power circuitry 137 may incertain embodiments comprise power management circuitry. Power circuitry137 may additionally or alternatively be operable to receive power froman external power source; in which case WD 110 may be connectable to theexternal power source (such as an electricity outlet) via inputcircuitry or an interface such as an electrical power cable. Powercircuitry 137 may also in certain embodiments be operable to deliverpower from an external power source to power source 136. This may be,for example, for the charging of power source 136. Power circuitry 137may perform any formatting, converting, or other modification to thepower from power source 136 to make the power suitable for therespective components of WD 110 to which power is supplied.

As described above, in NR WD 110 may be required to switch from a firstBWP (i.e., a source BWP) to a second BWP (i.e., a target BWP). The needfor WD 110 to switch BWP may cause problems with respect to RLM and RLF,such as those described above. As described in detail below, the variousembodiments described herein relate to actions performed by a WD (e.g.,WD 110) and the network (e.g., network node 160) in the context of RLMconfiguration and RLF upon BWP switching that may solve these and/orother problems related to BWP switching.

In certain embodiments, WD 110 (e.g., a UE) obtains one or more RLMconfigurations. Each RLM configuration may be associated with at leastone BWP. For example, the one or more RLM configurations may include anRLM configuration associated with a target BWP. In certain embodiments,network node 160 (e.g., a gNB) may determine the one or more RLMconfigurations.

WD 110 may obtain the one or more RLM configurations in any suitablemanner. As one example, WD 110 may be configured by network node 160with one or more RLM configurations. For instance, WD 110 may obtain theone or more RLM configurations by receiving the one or more RLMconfigurations in a message from network node 160. In some cases, themessage from network node 160 may be sent as part of network node 160configuring WD 110 to perform RLM on a BWP (e.g., a target BWP)according to an RLM configuration associated with that BWP. In certainembodiments, the message may include an indication of the RLMconfiguration associated with that BWP. In some cases, the indicationmay be included in an IE within a BWP configuration for the BWP. In somecases, the indication may be included in an IE within a serving cellconfiguration. In some cases, the indication may comprise a RLMconfiguration identifier.

As another example, WD 110 may obtain the one or more RLM configurationsby determining the one or more RLM configurations (e.g., according toone or more pre-defined rules). For instance, WD 110 may determine oneor more RLM configuration parameters. In some cases, the determinationmay be based on an active BWP or a set of active BWPs. In certainembodiments, network node 160 may configure WD 110 to determine the RLMconfiguration associated with a BWP according to the one or morepre-defined rules.

In certain embodiments, one of the obtained RLM configurations may be anactive RLM configuration. In certain embodiments, WD 110 may determinethat one of the RLM configurations is an active RLM configuration. WD110 may determine that one of the RLM configurations is an active RLMconfiguration in any suitable manner. As one example, WD 110 may beconfigured by network node 160 with an active RLM configuration. Inother words, one of the obtained one or more RLM configurations may beconfigured by network node 160 as an active RLM configuration. Asanother example, WD 110 may determine the active RLM configuration(e.g., based on a pre-defined rule).

In certain embodiments, one of the obtained one or more RLMconfigurations may be a default RLM reconfiguration. The default RLMconfiguration may be configured by the network (e.g., by network node160), specified by the standard, and/or determined by the WD 110 (forexample, based on a pre-defined rule). In some cases, the default RLMconfiguration may be associated with a default BWP. In some cases, thedefault RLM configuration may not be associated with a default BWP.

Each RLM configuration may include information related to RLM. Ingeneral, each RLM configuration includes a set of radio resources forperforming radio link monitoring within its associated BWP as well asone or more configuration parameters for performing RLM within itsassociated BWP. Examples of radio resources include CSI-RS resource, SSB(also known as SS/PBCH Block or SS Block), or other radio resourcessuitable for RLM. Examples of configuration parameters for performingRLM that may be included in the RLM configuration are filteringparameters (e.g., the N310, N311, N313, N314 counters or anothersuitable counter), RLF timer(s) (e.g. the T310, T311, T313, T314 RLFtimers or another suitable timer), an evaluation period, a number ofretransmissions before RLF is declared, a hypothetical channel/signalconfiguration, a mapping function between the measured link quality andhypothetical channel BLER, or other suitable configuration parameters.The information that may be included in an RLM configuration isdescribed in more detail below.

In certain embodiments, each RLM configuration may include one or acombination of the following types of information.

Each RLM configuration may include the RS type(s) that should bemonitored for RLM (i.e., PBCH/SS Block, CSI-RS or a combination ofCSI-RS resources and SSB resources).

Each RLM configuration may include the specific resources for theconfigured RS type to be monitored for RLM. As one example for cases inwhich CSI-RS resources are used, each RLM configuration may include thespecific RLM CSI-RS resources in time/frequency and the exact sequence.As another example for cases in which SS/PBCH Block resources are used,each RLM configuration may include the specific SS/PBCH Block indexes.In certain embodiments, the specific SS/PBCH Block indexes may bederived by WD 110. In certain embodiments, the specific SS/PBCH Blockindexes may be explicitly indicated. As another example for cases inwhich a combination of SSB and CSI-RS resources are used, each RLMconfiguration may include the combination of SSB and CSI-RS resources(e.g., the specific RLM CSI-RS resources in time/frequency and the exactsequence as well as the specific SS/PBCH Block indexes).

Each RLM configuration may include link and/or channel quality relatedthresholds (e.g., SINR thresholds and/or a pair of BLER thresholds forIS and OOS event generation). These parameters may change when BWPs arechanged.

Each RLM configuration may include one or more RLM/RLF-related timers orcounters (e.g., the T310 timer and the N310 counter). Other timers andcounters may be included in addition (or as an alternative), such as theother types of timers and counters described herein.

Each RLM configuration may include one or more parameters that determinethe mapping between SINR and BLER, or a mapping function, mapping rule,or mapping table. Note that the mapping to be used by WD 110 may beexplicitly configured or controlled by the network (e.g., by networknode 160).

Each RLM configuration may include a compensation factor to be appliedto SINR prior to mapping to a channel quality (e.g., a hypotheticalcontrol channel BLER). In certain embodiments, the compensation factormay depend, for example, on one or more of the BWP, type of RLMresources, BLER, measurement bandwidth for RLM, numerology (such assubcarrier spacing, symbol length, or cyclic prefix (CP) length),frequency, and other suitable criteria.

Each RLM configuration may include a link evaluation period for RLMand/or the number of samples to be used for the link evaluation.

Each RLM configuration may include one or more configuration parametersof the hypothetical channel (e.g., a hypothetical PDCCH), such as one ormore of bandwidth, aggregation level, DCI size, a number of symbols, aratio of control channel energy to SSS resource element (RE) energy, orother suitable configuration parameters.

In certain embodiments, the WD 110 may obtain an RLF/SCG failureconfiguration. In some cases, the RLF/SCG failure configuration may beincluded in the RLM configuration. In some cases, the RLF/SCG failureconfiguration may be separate from the RLM configuration. In such ascenario, WD 110 may obtain the RLF/SCG failure configuration in asimilar manner to that described above with respect to WD 110 obtainingthe one or more RLM configurations. In certain embodiments, each RLF/SCGfailure configuration may include one or more of the following: timers(e.g., one or more of timers T310, T311, T313, T314); and counters(e.g., one or more of counters N310, N311, N313, N314).

In certain embodiments, WD 110 determines that WD 110 is to switch froma source BWP to a target BWP. For example, WD 110 may receive aninstruction to switch from a source BWP to a target BWP (e.g., via DCI).WD 110 performs RLM on the target bandwidth part according to anobtained RLM configuration associated with the target BWP. In certainembodiments, upon activating a new BWP, WD 110 may activate a previouslyconfigured RLM configuration based on various rules and/or criteria.

In one example embodiment, one or more of the target BWP and the sourceBWP may be a DL BWP (e.g., for a paired spectrum or FDD). In anotherexample embodiment, one or more of the target BWP and the source BWP maybe a DL/UL BWP (e.g., for unpaired spectrum or TDD), where the DL BWPand UL BWP have the same frequency center and are activatedsimultaneously, even though they may have the same or differentbandwidth. In yet another example embodiment, one or more of the targetBWP and the source BWP may be an UL BWP, which potentially may alsoimpact how RLM/RLF is configured.

To illustrate the above, a specific example embodiment will now bedescribed. WD 110 may obtain K1 RLM configurations that are associatedto K2 BWP configurations (e.g., RLM configuration k1* is associated tothe BWP configuration k2*). As described above, WD 110 may obtain the K1RLM configurations based on a message received from network node 160and/or determine the K1 RLM configurations (e.g., based on a predefinedrule). WD 110 may determine (e.g., derive based on a pre-defined rule orthe standard or select from a set of pre-defined values) at least oneRLM configuration parameter for at least one RLM configuration out ofthe K1 RLM configurations. Upon triggering the activation of a given BWP(e.g., k2*), WD 110 activates the associated RLM configuration, k1*.

The RLM and BWP configurations may be associated in a variety of ways.As a first example, each RLM configuration can be provided as an IEwithin each BWP configuration. As a second example, each RLMconfiguration can be provided as an IE within the serving cellconfiguration and associated with an RLM configuration identifier, whereonly the RLM configuration identifier is part of each BWP configurationIE. This advantageously allows RLM configurations to be efficientlyconveyed in RRC signaling. As a third example, each RLM configurationcan be provided as an IE within the serving cell configuration, andthere may be a list of BWP IDs within each RLM configuration IE. The RLMconfiguration per BWP may be OPTIONAL fields in the BWP configuration inany of the above-mentioned cases. In other words, there can be acell-based default RLM configuration that is assumed if WD 110 isswitched to a BWP without the RLM configuration.

The configurations of the source (i.e., old) BWP and target (i.e., newactive) BWP may be the same or different in terms of RS type. Differentcombinations may exist as described in more detail below. As a firstexample, the RLM configuration associated with the source BWPconfiguration may define RS Type=SS Block and the RLM configurationassociated with the target BWP configuration may also define RS Type=SSBlock. In some cases, the new (i.e., target) SSB for RLM measurementsmay be in the same frequency position as the old (i.e., source) SSB. Insome cases, the new SSB for RLM measurements may be in a differentfrequency position than the old SSB. In some cases, the new SSB for RLMmeasurements may have the same time-domain pattern as the old SSB. Insome cases, the new SSB for RLM measurements may have a differenttime-domain pattern than the old SSB. In some cases, the new SSB for RLMmeasurements may have the same physical cell identifier (PCID) as theold SSB. In some cases, the new SSB for RLM measurements may have adifferent PCID than the old SSB. In some cases, the new SSB for RLMmeasurements may define the same RLM resources (i.e., SSB indexes) asthe old SSB. In some cases, the new SSB for RLM measurements may definedifferent RLM resources (i.e., SSB indexes) than the old SSB. These caneither be additional resources or fewer resources.

As a second example, the RLM configuration associated with the sourceBWP configuration may define RS Type=CSI-RS and the RLM configurationassociated with the target BWP configuration may define RS Type=CSI-RS.In some cases, the new CSI-RS resources for RLM measurements may be inthe same frequency position as the old CSI-RS resource. In some cases,the new CSI-RS resources for RLM measurements may be in differentfrequency position than the old CSI-RS resources. In some cases, the oldand new CSI-RS configuration may define the same CSI-RS measurementbandwidths. In some cases, the old and new CSI-RS configurations maydefine different CSI-RS measurement bandwidths. In some cases, the newCSI-RS resource(s) for RLM measurements may have the same time-domainpattern as the old CSI-RS resource(s) for RLM. In some cases, the newCSI-RS resource(s) for RLM measurements may have a different time-domainpattern than the old CSI-RS resource(s) for RLM. In some cases, the newCSI-RS resource(s) for RLM measurements may have the same sequence asthe old CSI-RS resource(s). In some cases, the new CSI-RS resource(s)for RLM measurements may have a different sequence than the old CSI-RSresource(s). In some cases, the new CSI-RS resources for RLMmeasurements may define the same RLM resources (i.e., CSI-RStime/frequency/sequence) as the old CSI-RS. In some cases, the newCSI-RS resources for RLM measurements may define different RLM resources(i.e., CSI-RS time/frequency/sequence) than the old CSI-RS.

In cases where the RLM RS is CSI-RS, WD 110 may be configured by thenetwork (e.g., network node 160) with one or multiple RLM configurationsbased on one or multiple sets of CSI-RS resource(s), possibly allocatedin different portions of the whole cell bandwidth (i.e., comprisingmultiple BWPs). Hence, upon switching to a new active BWP, WD 110 stopsusing previously-used CSI-RS resource(s) within the source BWP for RLM(i.e., WD 110 stops performing measurement(s) on the previously-usedCSI-RS resource(s) and stops mapping these to the BLER thresholds togenerate IS/OOS events) and starts using the configured CSI-RSresource(s) within the new BWP for RLM (i.e., WD 110 performs SINRmeasurements to be mapped to the configured BLER values).

In certain embodiments, multiple configured CSI-RS resources may liewithin the new BWP. In such a scenario, network node 160 may configureWD 110 to select one or more sets of radio resources to use to performRLM on the target BWP (e.g., based on a predefined rule). WD 110 mayselect one or more of the sets of radio resources to use to perform RLMon the target BWP (e.g., based on the pre-defined rule). WD 110 maydetermine which CSI-RS resources to use for RLM monitoring in anysuitable manner. In certain embodiments, this determination may be basedon a pre-defined rule (e.g., a rule governing which one WD 110 shoulduse for RLM monitoring). As one example, the rule may be that the WD 110selects the CSI-RS resource with the highest frequency component to usefor RLM monitoring. As another example, the rule may be that the WD 110performs RLM measurements across all the CSI-RS configured within theBWP. Alternatively, in certain embodiments WD 110 may be configured toarbitrarily choose one of the multiple configured CSI-RS resources forRLM monitoring.

Similarly, multiple configurations of SSBs and corresponding WD 110behavior are feasible when the RLM RS-type is set to SSB. In otherwords, network node 160 may configure WD 110 to select one or more setsof radio resources (in this instance, SSB resources) to use to performRLM on the target bandwidth part, and WD 110 may select one or more ofthe plurality of sets of radio resources to use to perform RLM on thetarget BWP part (e.g., based on a pre-defined rule such as thosedescribed above for scenarios in which multiple sets of CSI-RS resourcesare configured).

In certain embodiments, network node 160 may provide multiple RLM RSconfigurations associated with the same BWP (e.g., one or more RSconfigurations for each of the configured BWPs). For example, networknode 160 may provide WD 110 with one RLM configuration using SSB and oneRLM configuration using CSI-RS, both of which are associated with thesame BWP. As another example, network node 160 may provide WD 110 withmultiple RS configurations of the same RS-type (e.g., two RLMconfigurations that both use a CSI-RS configuration, or both use anSSB). In either example scenario, network node 160 may indicate (e.g.,in the DCI ordering the BWP switch) which of the RS configurationsassociated with the target BWP should be used for RLM. In certainembodiments, network node 160 may also activate a corresponding RS(unless, for example, it was already activated for another WD using thesame BWP).

In certain embodiments, the use of different BLER thresholdconfigurations could be handled in a similar way. In other words, theremay be multiple BLER threshold configurations associated with the sameBWP, and network node 160 may provide WD 110 with an indication of whichof the multiple BLER threshold configurations should be used with theBWP for RLM.

Alternatively, in certain embodiments network node 160 may provide alist of RLM RS configurations without association with BWPs. In such ascenario, network node 160 may indicate in the DCI ordering a BWP switchwhich of the listed RS configurations should be used for RLM in the newBWP. Different BLER threshold configurations could also be handled inthe same way.

In addition to the above-described examples, there are a variety ofother ways in which an RLM/RLF configuration can be associated with aBWP, including the example rules described below. These rules may beused by the network (e.g., network node 160) configuring RLM/RLF andBWPs (or the association between BWPs and RLM/RLF configurations) or byWD 110 selecting the appropriate RLM/RLF configuration upon changing theset of active BWPs. Examples of rules that may be used for associatingan RLM/RLF configuration with a BWP in certain embodiments are describedin more detail below.

As a first example rule, in certain embodiments RLM is based on a firstbandwidth (BW1) (e.g., SSB for SSB-based RLM or CSI-RS for CSI-RS-basedRLM) when a first BWP (BWP1) is active, while RLM is based on a secondbandwidth (BW2) (e.g., SSB for SSB-based RLM or CSI-RS for CSI-RS-basedRLM) when a second BWP (BWP2) is active. In such a scenario, the firstbandwidth is less than or equal to the second bandwidth (i.e., BW1<=BW2)and the bandwidth of BWP1 is not larger than the bandwidth of BWP2.

As a second example rule, in certain embodiments a first type of RLM RS(e.g., signals comprised in SS Block) is used when the SS Block iscomprised within a BWP, while a second type of RLM RS (e.g., CSI-RS) isused otherwise.

As a third example rule, in certain embodiments a first type ofthresholds, timers, and/or counters is used when RLM is based on a firstRLM RS type (e.g., SS Block-based), while a second type of threshold,timers, and/or counters is used when RLM is based on a second RLM RStype (e.g., CSI-RS).

As a fourth example rule, in certain embodiments a first compensationfactor is applied when a first BWP is active, while a secondcompensation factor is applied when a second BWP is active. In such ascenario, at least one of the first and the second compensation factorschanges the RLM measurement (e.g., SINR) to a different value (e.g.,non-zero compensation factor if it is added to SINR or not equal to 1 ifit scales the SINR).

As a fifth example rule, in certain embodiments a first set ofconfiguration parameters (e.g., bandwidth, aggregation level, DCI size,number of symbols, ratio of control channel energy to SSS RE energy,etc.) of the hypothetical channel (e.g., hypothetical control channel)is used when a first BWP is active, while a second set of configurationparameters of the hypothetical channel is used when a second BWP isactive.

As a sixth example rule, in certain embodiments a longer RLM evaluationperiod for a first RLM RS (e.g., with a more sparse RE structure in timeand/or frequency) and a shorter RLM evaluation period for a second RLMRS (e.g., with a more dense RE structure in time and/or frequency) areused for the same BLER. Furthermore, in certain embodiments theevaluation period may restart upon changing the RLM RS due to BWPchange, while the RLM/RLF related timers and counters may continue.

As a seventh example rule, in certain embodiments the evaluation periodis extended if the bandwidth of the hypothetical channel and/or BWP isreduced, while the evaluation period is reduced if the bandwidth of thehypothetical channel and/or BWP increases. In certain embodiments, theevaluation period may be the longest between the evaluation periodscorresponding to the new and old BWP during the transition time (i.e.,when the evaluation period does not restart upon the BWP change).

As described above, performing RLM entails using measurements togenerate OOS and IS events. In certain embodiments, WD 110 may performspecific actions related to measurements when it needs to change BWP.These actions may relate to, for example whether (and how) measurementsperformed in a previous BWP can be used in a newly activated BWP, howthe OOS and IS events generated in the previous BWP can be used, and howthe WD 110 and network node 160 manage counters (e.g., the N310, N311,N313, N314 counters) and timers (e.g., the T310, T311, T313 and T314timers) for these events. Various example embodiments related to how WD110 handles its measurements when it changes BWP are described in detailbelow.

For example, in some cases the hypothetical channel configuration usedfor RLM may be different for the new BWP. In such a scenario, WD 110 mayupdate the hypothetical channel configuration used for RLM. Similarly,other variables such as the RLM measurement bandwidth, the BLER or BLERpair used for RLM, the compensation factor, and the mapping between anRLM measurement (e.g., SINR) and BLER may be different for the new BWP.If the RLM measurement bandwidth is different for the new BWP, WD 110may change its RLM measurement bandwidth. If the BLER or BLER pair usedfor RLM are different for the new BWP, WD 110 may update the BLER orBLER pair used for RLM. If the compensation factor for the new BWP isdifferent, WD 110 may apply a different compensation factor. If themapping between an RLM measurement and BLER is different for the newBWP, WD 110 may use a new mapping between an RLM measurement and BLER.

As another example, in some cases the evaluation period for the newlyactive BWP may be different. In such a scenario, WD 110 may change theRLM evaluation period. For instance, the evaluation period may bechanged as described above in relation to the sixth and seventh examplerules for associating an RLM/RLF configuration with a BWP.

In some cases, the same RS type and resources may be used in the newlyactive BWP (i.e., target BWP). In such a scenario, WD 110 may continueusing previously-performed measurements or measurement samples togenerate OOS and IS events (i.e., WD 110 keeps counting). In certainembodiments, WD 110 maintains the counter variables (e.g., N310, N311,N313, N314). Thus, the counter variables keep increasing/decreasingbased on the generated OOS and/or IS events. In other words, from ahigher layer perspective how IS/OOS events are generated remainstransparent. In certain embodiments, network node 160 may configure WD110 to use one or more of previously-performed measurements andpreviously-performed measurement samples to generate OOS and IS eventswhen the same RS type and resources are used in the newly active BWP.

In some cases, however, RLM measurements may not be able to be reusedwhen a new BWP is activated. If the RLM measurements cannot be reusedwhen a new BWP is activated, WD 110 may restart one or more timers orcounters. Otherwise (i.e., if the RLM measurements can be reused), WD110 may continue using at least one of the timers or counters (e.g., asdescribed above).

When different resources are used in the newly active BWP, there are avariety of ways in which WD 110 can handle the counters and timers usedfor generating IS/OOS events. Different example embodiments detailingways in which WD 110 behaves when different resources are used in thenewly active BWP are described in more detail below.

In one example embodiment, if different RLM RS are used for differentBWPs, WD 110 applies a relation function to measurements to allow theRLM evaluations to continue and to allow for continuing the timers andcounters. In one example, the relation function may be an offset appliedto SINR based on a first RLM RS compared to that based on a second RLMRS. In certain embodiments, network node 160 may configure WD 110 toapply a relation function to one or more previously-performedmeasurements and previously-performed measurement samples to generateOOS and IS events without resetting a RLF timer or a RLF counter whendifferent RLM RS are used in the newly active BWP.

In another example embodiment, WD 110 resets at least one of the timersor counters when the RLM RS is different upon a change of BWP. Incertain embodiments, network node 160 may configure WD 110 to reset atleast one of a RLF timer and a RLF counter when different resources areused in the newly active BWP.

In another example embodiment, WD 110 resets one set of timers andcounters (e.g., for RLM OOS) and allows another set of timers andcounters to continue (e.g., for RLM IS). In certain embodiments, networknode 160 may configure WD 110 to reset a set of RLF timers and RLFcounters (e.g., for OOS events) and configure WD 110 to allow a set ofRLF timers and RLF counters (e.g., for IS events) to continue whendifferent RLM RS are used in the newly active BWP.

In another example embodiment, WD 110 allows the timers to continue butnot the counters. In certain embodiments, network node 160 may configureWD 110 to reset one or more RLF timers without resetting any RLFcounters when different RLM RS are used in the newly active BWP.

In another example embodiment, WD 110 applies an offset (e.g., to extendthe time or increase the number of allowed RLM physical layer reportsbefore triggering an action) to at least one counter or timer. Incertain embodiments, network node 160 may configure WD 110 to apply anoffset to at least one counter or timer when different RLM RS are usedin the newly active BWP.

As described above, WD 110 may obtain an RLF/SCG failure configuration,and each RLF/SCG failure configuration may include one of the followingor a combination of these parameters: timers (e.g., one or more oftimers T310, T311, T313, T314); and counters (e.g., one or more ofcounters N310, N311, N313, N314). Various embodiments related to theconfiguration of the RLF/SCG failure parameters are described in moredetail below.

In some cases, at least one of the timers that trigger RLF or SCGFailure (e.g., timer T310 or T313) may be running when a BWP switchingis triggered. Various example actions that may be performed by WD 110 ifany of the timers that trigger RLF or SCG Failure are running when BWPswitching is triggered are described in more detail below. For purposesof the following examples, it should be assumed that one of the timersthat trigger RLF or SCG failure are running when BWP switching istriggered.

As a first example, in some cases the RLM RS type may be SSB in both theold (i.e., source) BWP and the new (i.e., target) BWP, and the new BWPmay have no new SSB associated to it within the newly active BWP. Inother words, WD 110 may be configured to continue using the same SSB forRRM measurements and RLM. In such a scenario, in certain embodiments WD110 performs the following actions: WD 110 does not reset the timer(s);WD 110 does not discard previously-performed measurements; WD 110 doesnot discard previously-generated IS/OOS events; and WD 110 continuesincrementing the counter(s).

As a second example, in some cases the RLM RS type in the old BWP mayhave been either SSB or CSI-RS and the RLM RS type may be SSB in the newBWP. Additionally, the new BWP may have a new SSB associated with itwithin the newly active BWP to be used for RRM measurements and/or RLM.In such a scenario, in certain embodiments WD 110 performs the followingactions: WD 110 resets the timer(s); WD 110 discardspreviously-performed measurement(s); WD 110 discardspreviously-generated IS/OOS event(s); and WD 110 resets the counter(s).

As a third example, in some cases the RLM RS type may be CSI-RS in boththe old and the new BWP, and the new BWP may have no new CSI-RSconfiguration associated to it within the newly active BWP. In otherwords, WD 110 may be configured to continue using the same CSI-RSconfiguration for RRM measurements and RLM. In such a scenario, incertain embodiments WD 110 performs the following actions: WD 110 doesnot reset the timer(s); WD 110 does not discard previously-performedmeasurement(s); WD 110 does not discard previously-generated IS/OOSevent(s); and WD 110 keeps incrementing the counter(s).

As a fourth example, in some cases the RLM RS type in the old BWP mayhave been either SSB or CSI-RS, and the RLM RS type may be CSI-RS in thenew BWP. Additionally, the new BWP may have a new CSI-RS configurationassociated with it within the newly active BWP. In such a scenario, incertain embodiments WD 110 performs the following actions: WD 110 doesnot reset the timer(s); WD 110 does not discard previously-performedmeasurement(s); WD 110 does not discard previously generated IS/OOSevent(s); WD 110 keeps incrementing the counter.

As a fifth example, in some cases the RLM RS type in the old BWP mayhave been either SSB or CSI-RS, and the RLM RS type may be CSI-RS in thenew BWP. Additionally, the new BWP may have a new CSI-RS configurationassociated with it within the newly active BWP. In such a scenario, incertain embodiments WD 110 performs the following actions: WD 110 resetsthe timer(s); WD 110 discards previously-performed measurement(s); WD110 discards previously generated IS/OOS event(s); and WD 110 resets thecounter(s).

Note that with respect to the various example embodiments describedabove related to actions performed by WD 110 when at least one of thetimers that trigger RLF or SCG failure are running when BWP switching istriggered, the actions described as performed by WD 110 may be performedin any order and the present disclosure is not limited to performing theactions in the order described above.

Moreover, the above-described actions that may be performed by WD 110 incertain scenarios are not intended to be limiting or exhausting. In somecases, other actions by WD 110 may be appropriate in conjunction withWBP switching for different RLM RS type cases. Thus, in certainembodiments the opposite behavior (or variations in the above-describedexample embodiments) may be used in some switching cases. Hence, inother embodiments, when WD 110 switches from one BWP to another, wherethe new BWP has a new RS type or a new configuration for the same RStype, WD 110 may keeps timer(s) and counter(s) running and keeppreviously-performed measurement(s) and previously generated IS/OOSevent(s). In certain embodiments, this could be broken down in finergranular embodiments. For example, WD 110 may keep timer(s), counter(s),measurement(s) and event(s) if the RS type is the same in the new BWP,but otherwise not.

In certain embodiments, the actions taken by WD 110 on resetting thetimer(s) and/or counter(s) or maintaining them based on an update to RLMresource configurations may be configured by the network. The logicbehind not changing the RLM state variables is that WD 110 still remainson the same cell. Hence, if WD 110 had trouble synchronizing and hadgood enough channel quality in the old BWP, changing the BWP is not verylikely to change that. On the other hand, as a BWP change leads to (orat least may lead to) a PDCCH configuration update (e.g., CORESETconfiguration update), which might change the beamforming properties ofPDCCH also, the network may want to reset the state variables related toRLM and RLF.

In certain embodiments, the network (e.g., network node 160) mayconfigure the actions to be taken by WD 110 with respect to resetting ormaintaining the timer(s) and/or counter(s) (such as the various actionsby WD 110 described above) in a variety of ways. In certain embodiments,the configuration of the actions performed by WD 110 could be providedwhen the BWPs are configured. For example, in the form of a singlegeneral action rule configuration that could be applied to all BWPswitches. In certain embodiments, the general action rule configurationmay specify that the same actions should be performed irrespective ofBWPs involved in the switch. In certain embodiments, the general actionrule configuration may specify that different actions should beperformed depending on the type of BWP switch (e.g. in terms of thedifferent scenarios above, i.e. change of RS type or not, change of RSresource configuration or not). Alternatively, in certain embodimentsthe network may configure separate actions associated with eachconfigured BWP. For example, the actions associated with a particularBWP may be performed when WD 110 switches to that particular BWP. Asanother example, the actions associated with a particular BWP maybeperformed when the UE switches from that particular BWP to another BWP.As still another example, network node 160 (e.g., a gNB) may provide alist of action configurations to WD 110. The list of actionconfigurations may not include BWP associations. Network node 160 mayindicate (e.g., in the DCI ordering a BWP switch) which of the listedaction configurations WD 110 should apply in conjunction with theconcerned BWP switch.

In certain embodiments, WD 110 may estimate the radio link quality tomonitor the DL link quality (e.g., based on CSI-RS or SSB signals) forthe purpose of RLM (e.g., for OOS and IS evaluations) in at least twodifferent BWPs over at least a partly overlapping time period (e.g.,evaluation periods). In some cases, this may be referred to herein as“parallel monitoring” or “partial parallel monitoring” of DL linkqualities in different BWPs for RLM.

In some cases, the quality of a best beam at every sample may berelevant to generating OOS/IS events. Examples of OOS and IS evaluationperiods for CSI-RS based RLM are 100 ms and 200 ms, respectively (e.g.,when OOS/IS evaluation is based on DL link quality measured on CSI-RS).Examples of OOS and IS evaluation periods for SSB based RLM are 3*Tsssand 6*Tsss, respectively (e.g., when OOS/IS evaluation is based on DLlink quality measured on SSB signals and where Tsss is the SS burstperiodicity configured at WD 110 for RLM.

As described in more detail below, according to one example embodimentWD 110 may perform parallel monitoring of the DL link qualities in twoor more BWPs regardless of the rate with which these BWPs are activated.In another example embodiment, WD 110 may perform parallel monitoring ofthe DL link qualities in two or more BWPs depending on the rate at whichthese BWPs are activated. For example, WD 110 may perform parallelmonitoring of the DL link qualities in any two BWPs provided that the UEis configured to activate each BWP for a certain time period at leastonce every T1 time units (e.g., T1=10 ms). For example, this rule willrequire WD 110 to monitor the DL link quality in two or more BWPs inparallel only if these BWPs remain active continuously for a shorterduration (e.g., shorter than the evaluation period of DL radio linkquality).

In certain embodiments, WD 110 may be configured to perform parallelevaluation (i.e., during at least a partly overlapping time period) ofDL link quality in two or more BWPs in parallel selectively and/or basedon one or more criteria. The criteria may be any suitable criteria.Examples of criteria include but are not limited to: a duration overwhich the UE remains active in one or more configured BWPs; and a ratewith which WD 110 is switched between different active BPWs. Morespecifically, WD 110 may be further configured to perform parallelevaluation of DL link quality in two or more BWPs in parallel over atleast partially overlapping time period based on the duration over whichone or more of the BWPs remain active for the UE.

To illustrate, consider the following example embodiment. For purposesof this example, assume that WD 110 is configured (e.g., via RRC) withtwo BWPs: a first BWP (BWP1) and a second BWP (BWP2). Assume furtherthat in one time instance, WD 110 can be configured (e.g., via DCI) withonly one active BWP (i.e., the activated or active BWP of WD 110 iseither BWP1 or BWP2 in the current example). If WD 110 is configuredwith active BWP1 or active BWP2 over a duration shorter than a certaintime threshold (Ta), then WD 110 may perform DL radio link monitoring ofDL signals in both BWP1 and BWP2 whenever WD 110 becomes active in therespective BWP. But, if WD 110 is configured with active BWP1 or activeBWP2 over a duration equal to or larger than the time threshold Ta, thenWD 110 performs DL RLM of DL signals only in the BWP which remainsactive after Ta. Examples of Ta include 10 ms, 100 ms, etc.

In the former case (when BWP1 or BWP2 is active for less than the timethreshold Ta), in certain embodiments WD 110 may further evaluate theOOS or IS detection based on a combination of the DL radio linkqualities measured across BW1 and BW2. As another example, in certainembodiments WD 110 may independently evaluate OOS and IS detection basedon the radio link qualities measured across BW1 and BW2. In certainembodiments, whether WD 110 should use a combined metric for OOS and ISdetection or independently apply DL radio link qualities for OOS and ISdetection may be pre-defined as a rule in the standard. In certainembodiments, whether WD 110 should use a combined metric for OOs and ISdetection or independently apply DL radio link qualities for OOS and ISdetection may be configured at the UE by network node 160 (e.g., viaRRC, MAC, and/or DCI over PDCCH or some other suitable manner). Examplesof metrics to obtain combination of the DL radio link qualities includebut are not limited to average, maximum, minimum, or some other suitablemetric. This mechanism will enhance RLM performance and lead to powersaving at WD 110 since WD 110 does not need to perform parallelevaluation for OOS and IS detection in multiple BPW all the time(instead, it may do it selectively).

In certain embodiments, WD 110 may be configured with N BWPs. One of theconfigured N BWPs may be configured as a default BWP. In such ascenario, in certain embodiments WD 110 may always estimate the radiolink quality to monitor DL link quality (e.g., based on CSI-RS or SSBsignals) in the default BWP. Additionally, in certain embodiments WD 110may monitor the radio link quality of the current active BWP when thecurrent active BWP is not the default BWP. In some cases, a timer may beused (e.g., WD 110 may go back to the default BWP if WD 110 cannotreceive DCI in the active BWP for certain time T). If WD 110 ismonitoring radio link quality from two different BWPs, the OOS and ISindications may be associated with an indication (e.g., a tag)indicating which BWP caused the indication.

In certain embodiments, WD 110 may be configured to store BWPconfiguration information (e.g., related to RLM configuration and RLF)in the RLF report that can be transmitted to the network uponre-establishment (e.g., after RLF occurs). In certain embodiments,information may be stored when RLF occurs in a given BWP. WD 110 mayinclude in an RLF report the BWP configuration when the RLF hasoccurred. In certain embodiments, WD 110 may also include otherinformation, such as whether the RLF occurred in conjunction with a BWPswitch and, if so, whether the switching was caused by a DCI signalingor a timer. In certain embodiments, the RLF report may also includeinformation about the old BWP, in case the RLF occurred in conjunctionwith a switch from an old to a new BWP. In certain embodiments, some orall of this information may be included (additionally or alternatively)in an RRC Connection Re-establishment request.

In certain embodiments, network node 160 may configure WD 110 in one ormore of the various ways described above. In addition to configuring WD110 as described above, in certain embodiments network node 160 maytransmit different reference signals in specific resource(s). Forexample, network node 160 may transmit different reference signals inspecific resource(s) per configured BWP. As another example, networknode 160 may activate certain reference signals upon the activation of agiven BWP. For instance, in certain embodiments the transmission of theRLM RS may be triggered by the activation of the BWP for at least one WD(e.g., by the fact the network node starts to transmit PDCCH in thatnewly activated BWP for that WD).

The following section illustrates an example approach to how one or moreof the above-described embodiments may be implemented into a standard.The description below reflects one possible approach, and the presentdisclosure is not limited to the examples described below.Modifications, additions, or omissions may be made to the exampleapproach described below without departing from the scope of the presentdisclosure.

There are two options for how to do RLM when there are multiple BWPsconfigured for a UE. A first option is to monitor the current active BWPall the time. A second option is to monitor RLM dedicated BWPs. Asagreed in RAN1, both SSB and CSI-RS can be configured as RLM RS. Sincenot each BWP can be configured with SSB however each BWP can beconfigured with CSI-RS, then how to do RLM could be different per RS. Asagreed in RAN2, there is only one cell-defining SSB in a carrier. Thecell defining SSB is considered as the time reference of the servingcell, and for RRM serving cell measurements based on SSB. If SSB isconfigured as RLM RS, it may be beneficial to follow similar principlesas for serving cell RRM measurement. That is, cell-defining SSB is usedfor RLM. This means when there is no cell-defining SSB within thecurrent active BWP, a UE has to switch to the BWP with cell-defining SSBfor RLM purpose. This is also the case for RRM measurement. That is,when UE need to do serving cell RRM measurement, and SSB is not withinactive BWP, then the UE need to switch to the BWP with cell-defining SSBfor RRM measurement. According to RAN1, measuring on a RS not within UEactive BWP means a gap is needed. Thus, for SSB based RLM, RLM is in theBWP with cell-defining SSB. RLM is carried in measurement gap whenactive BWP does not have cell-defining SSB.

For CSI-RS based RLM, each active BWP must be configured with CSI-RS.Therefore it is quite natural that RLM is in the active BWP all thetime. In other words, for CSI-RS based RLM, RLM can always be in activeBWP.

Since both SSB based and CSI-RS based RLM need be supported, it isproposed that both RLM in active BWP and RLM in designated BWP should besupported and which one to choose depends on which RS is configured asRLM RS. As SSB based RLM is not BWP dependent, the configuration of RLMrelated parameters can be at cell level. While as CSI-RS based RLM isBWP dependent, the UE need to know the CSI-RS resource to monitor inactive BWP, therefore, besides some common parameters (e.g., timers andconstants that are shared by different BWP), there should be some BWPspecific RLM configuration (e.g., where is the CSI-RS resource tomonitor). Thus, it is proposed that CSI-RS based RLM includes both cellgroup and BWP specific configuration.

With respect to beam failure/recovery and RLF triggering, it should beconsidered whether beam failure related events can explicitly be part ofit, considering the following RAN1 agreements: NR should strive toprovide aperiodic indication(s) based on beam failure recovery procedureto assist radio link failure (RLF) procedure, if same RS is used forbeam failure recovery and RLM procedures. As a first example, aperiodicindication(s) based on beam failure recovery procedure can reset/stopT310. As a second example, aperiodic indication(s) based on failure ofbeam recovery procedure. It is for further study the use of aperiodicindication(s) based on beam failure recovery procedure to assist RLFprocedure if different RS is used.

That is, there might be aperiodic indication from L1 which indicateeither success or failure of beam failure recovery procedure. How to usesuch aperiodic indication in RLM/RLF procedure need be settled. The beamfailure and recovery procedure could be summarized as follows: UEmonitors configured DL beam(s)/beam pair(s) and based on that UE candetect beam failure; upon detecting the failure the UE can select new DLbeam(s)/pairs (which can either be from the same cell or from adifferent cell, if configured); upon selecting new beam(s) UE triggers abeam recovery attempt by notifying the network (UL message); UE monitorsa network response to finally declare a successful recovery.

Thus, it may be useful to provide aperiodic indication(s) based on beamfailure recovery procedure to assist radio link failure (RLF) procedure,if same RS is used for beam failure recovery and RLM procedures. Itneeds to be decided whether such aperiodic indicator can influenceRLM/RLF or not, and if so, how. If it is assumed that a successful beamrecovery (possibly indicated by the reception of the network message onthe selected beam) will lead to the generation of IS events, and, oncethe UE starts to measure the RS used for RLM after a successfulrecovery, the number of IS events will likely increase and at somepoint, the RLF timer should be stopped due to that. However, if T310 isclose to expire when beam recovery is successful, despite the fact thatit is a matter of time to detect the recovery of the link, the UE maydeclare RLF. For that reason, it can be argued that the detection of asuccessful recovery should immediately stop the RLF timer. However,although a successful beam recovery indicates that the link is verylikely to be recovered, periodic IS events are probably a safermechanism where the higher layers can make sure the link has not onlybeen recovered but is also stable over time. Thus, the possibility toconfigure the UE to not only stop the RLF timer upon the occurrence of asuccessful beam recovery but also based on aperiodic IS indicationgenerated due to beam recovery plus a number of configurable periodic ISevents (which can be smaller value than the counter equivalent to N311in LTE) should be considered. At some extreme case, there maybe notenough periodic IS event to stop RLF timer even beam failure recovery issuccessful. Thus, it is proposed that successful beam recovery can beused together with periodic IS to stope RLF timer.

Regarding the failure of beam failure recovery, assuming that this onlymeans from lower layer perspective, no further beam failure recoveryprocedure will continue. Therefore whether UE can recovery its linkafter sending indication of failure of beam failure recovery is notclear. If it is assumed that this depends on the number of beam failurerecovery procedure attempts or duration of this this beam failurerecovery procedure. If the number of attempts is small, or the durationof this beam failure recovery procedure is short, quite probably UE canstill recover its link even it does not continue beam failure recoveryprocedure. For example, UE is blocked by an obstacle, and later thisobstacle is removed. Therefore, it is not reasonable to declare RLFimmediately when receiving indication that beam recovery is failed insome case. On the other hand, it may be also not reasonable notconsidering such indicator in some other case. Whether UE can recoverits link after receiving indication of failure of beam failure recoveryis scenario dependent. It is proposed that failure of beam recovery canbe used together with periodic OOS to either start T310 (if it hasn'tbeen started), or declare RLF.

Besides, indication of success or failure of beam recovery, the attemptto recovery beam failure can be also be considered for RLM/RLFprocedure. A possible scenario is that the UE detects a beam failure andstarts the preparation for beam recovery, e.g., by selecting a new beambefore sending an associated UL recovery request. During that process,the RLF timer may be running so that while the UE is still trying torecover, an RLF could potentially be declared, despite the highpotential of a successful procedure e.g. if the UE has selected a newbeam that is strong enough and stable. If as proposed for the successfulcase the UE also stops the RLF timer even at the recovery attempt, andthe attempt is not successful, it will take a longer time until the RLFtimer starts again (i.e. based on OOS events) and the UE would beunnecessarily unreachable for much longer. Hence, to avoid the earlystop of the RLF timer, a possibility could be to put it on hold duringthe recovery attempt. If beam failure recovery is successful, proposal 1can be applied, if, if not successful, proposal 2 can be applied. It isproposed that beam recovery attempt can be used to put the RLF timer onhold.

In LTE, the RLF modelling has two phases. The first phase occurs beforethe RLF timer is triggered in LTE and the second phase starts after.Among the open issues is the existence of a second phase, after the RLFtimer expires. In LTE, a second timer is triggered and UE-basedmobility/cell reselection is allowed, before Re-establishment istriggered.

It is proposed that when the RLF timer expires, the “Second phase” timerstarts and the UE is allowed to perform UE-based mobility (i.e. cellreselection).

In LTE, when the RLF timer expires, RRC connection re-establishmentprocedure is triggered, where the UE first performs cell reselection. Ifthe new selected cell is still an LTE cell, UE initiates random accessprocedure on that cell, and then sendsRRCConnectionReestablishmentRequest message towards the network. If thenew selected cell is an inter-RAT cell, then UE should perform theactions upon leaving RRC_CONNECTED.

In NR, an additional aspect related to the second phase that should befurther discussed concerns the case where the UE re-selects to a cellfrom which it has been previously configured to perform beam recovery.In other words, the network can configure the UE to upon beam failure toeither select a beam from the PCell or to select a beam from anothercell. After RLF is declared, re-selects to one of these configuredcells, there is no reason not to perform beam recovery to one of thesecells instead of the usual RRC Connection Re-configuration.

An additional aspect to consider in NR is the possibility that the uponRLF the UE re-selects to an LTE cell. If the new selected cell is an LTEcell which connects to Next Generation Core, we think it is notnecessary for UE to leave RRC_CONNECTED state and do cell selection fromscratch. UE should continue with RRC re-establishment procedure as wellinstead of leaving RRC_CONNECTED even though this new selected cell isan inter-RAT cell. This is reasonable as UE can build up its context inLTE cell from old NR cell as the two cells are using same core network.If the new selected cell is a LTE cell which connects to legacy EPC orother inter-RAT cell, then UE should perform actions upon leavingRRC_CONNECTED. It is proposed that when UE encounter RLF in NR andreselect to an NR cell or an LTE cell which connects to 5GC, RRCconnection re-establishment procedure is applied. Otherwise, UE performactions upon leaving RRC_CONNECTED.

FIG. 7 is a flowchart of a method 700 in a UE, in accordance withcertain embodiments. Method 700 begins at step 701, wherein the UEobtains one or more radio link monitoring configurations, each radiolink monitoring configuration associated with at least one bandwidthpart.

In certain embodiments, obtaining the one or more radio link monitoringconfigurations may comprise receiving the one or more radio linkmonitoring configurations in a message from a network node. In certainembodiments, obtaining the one or more radio link monitoringconfigurations may comprise determining the one or more radio linkmonitoring configurations according to one or more pre-defined rules.

In certain embodiments, each radio link monitoring configuration maycomprise: a set of radio resources for performing radio link monitoringwithin its associated bandwidth part; and one or more configurationparameters for performing radio link monitoring within its associatedbandwidth part.

In certain embodiments, the set of radio resources may comprise a CSI-RSresource. In certain embodiments, the set of radio resources maycomprise a SSB.

In certain embodiments, the one or more configuration parameters forperforming radio link monitoring within its associated bandwidth partmay comprise one or more of: one or more filtering parameters; one ormore radio link failure timers; an evaluation period; a number ofretransmissions before radio link failure is declared; a hypotheticalchannel configuration; a hypothetical signal configuration; and amapping function for a measured link quality and a hypothetical channelblock error rate. In certain embodiments, the one or more configurationparameters for performing radio link monitoring within its associatedbandwidth part may comprise one or more filtering parameters and the oneor more filtering parameters may comprise one or more of N310, N311, andN313, N314 counters. In certain embodiments, the one or moreconfiguration parameters for performing radio link monitoring within itsassociated bandwidth part may comprise one or more radio link failuretimers and the one or more radio link failure timers may comprise one ormore of T310, T311, T313, and T314 timers.

In certain embodiments, at least one of the obtained one or more radiolink monitoring configurations may comprise a default radio linkmonitoring configuration. In certain embodiments, the default radio linkmonitoring configuration may be associated with a default bandwidthpart.

At step 702, the UE determines that the UE is to switch from a sourcebandwidth part to a target bandwidth part.

At step 703, the UE performs radio link monitoring on the targetbandwidth part according to an obtained radio link monitoringconfiguration associated with the target bandwidth part.

In certain embodiments, the method may comprise performing monitoring ofa downlink channel quality of a first bandwidth part and a secondbandwidth part. In certain embodiments, the performing monitoring maycomprise: estimating, during a first period of time, a radio linkquality of the first bandwidth part according to a radio link monitoringconfiguration associated with the first bandwidth part; and estimating,during a second period of time, a radio link quality of the secondbandwidth part according to a radio link monitoring configurationassociated with the second bandwidth part, wherein the second period oftime at least partially overlaps with the first period of time. Incertain embodiments, the first bandwidth part may comprise the sourcebandwidth part and the second bandwidth part may comprise the targetbandwidth part. In certain embodiments, the monitoring may be triggeredbased on an activation rate of one or more of the first bandwidth partand the second bandwidth part.

In certain embodiments, the radio link monitoring configurationassociated with the target bandwidth part may comprise a plurality ofsets of radio resources, and the method may further comprise selectingone or more of the plurality of sets of radio resources to use toperform radio link monitoring on the target bandwidth part based on apre-defined rule.

In certain embodiments, a plurality of radio link monitoringconfigurations may be associated with the target bandwidth part, and themethod may further comprise receiving an instruction via downlinkcontrol information to use one of the plurality of radio link monitoringconfigurations to perform radio link monitoring on the target bandwidthpart.

In certain embodiments, a radio link monitoring configuration associatedwith the source bandwidth part and the radio link monitoringconfiguration associated with the target bandwidth part may use the sameradio resources, and performing radio link monitoring on the targetbandwidth part according to the obtained radio link monitoringconfiguration associated with the target bandwidth part may compriseusing one or more of previously-performed measurements andpreviously-performed measurement samples to generate out-of-sync andin-sync events.

In certain embodiments, a radio link monitoring configuration associatedwith the source bandwidth part and the radio link monitoringconfiguration associated with the target bandwidth part may usedifferent radio resources. In certain embodiments, performing radio linkmonitoring on the target bandwidth part according to the obtained radiolink monitoring configuration associated with the target bandwidth partmay comprise applying a relation function to one or more ofpreviously-performed measurements and previously-performed measurementsamples to generate out-of-sync and in-sync events without resetting aradio link failure timer or a radio link failure counter. In certainembodiments, performing radio link monitoring on the target bandwidthpart according to the obtained radio link monitoring configurationassociated with the target bandwidth part may comprise resetting atleast one of a radio link failure timer and a radio link failurecounter. In certain embodiments, resetting at least one of a radio linkfailure timer and a radio link failure counter may comprise resetting aset of radio link failure timers and radio link failure countersassociated with radio link monitoring for out-of-synch events andallowing a set of radio link failure timers and radio link failurecounters associated with radio link monitoring for in-synch events tocontinue. In certain embodiments, resetting at least one of a radio linkfailure timer and a radio link failure counter may comprise resettingone or more radio link failure timers without resetting any radio linkfailure counters.

FIG. 8 is a schematic block diagram of a virtualization apparatus, inaccordance with certain embodiments. More particularly, FIG. 8illustrates a schematic block diagram of an apparatus 800 in a wirelessnetwork (for example, the wireless network shown in FIG. 6). Theapparatus may be implemented in a wireless device (e.g., wireless device110 shown in FIG. 6. Apparatus 800 is operable to carry out the examplemethod described with reference to FIG. 7 and possibly any otherprocesses or methods disclosed herein. It is also to be understood thatthe method of FIG. 7 is not necessarily carried out solely by apparatus800. At least some operations of the method can be performed by one ormore other entities.

Virtual Apparatus 800 may comprise processing circuitry, which mayinclude one or more microprocessor or microcontrollers, as well as otherdigital hardware, which may include digital signal processors (DSPs),special-purpose digital logic, and the like. The processing circuitrymay be configured to execute program code stored in memory, which mayinclude one or several types of memory such as read-only memory (ROM),random-access memory, cache memory, flash memory devices, opticalstorage devices, etc. Program code stored in memory includes programinstructions for executing one or more telecommunications and/or datacommunications protocols as well as instructions for carrying out one ormore of the techniques described herein, in several embodiments. In someimplementations, the processing circuitry may be used to cause receivingunit 802, determining unit 804, communication unit 806, and any othersuitable units of apparatus 800 to perform corresponding functionsaccording one or more embodiments of the present disclosure.

In certain embodiments, apparatus 800 may be a UE. As illustrated inFIG. 8, apparatus 800 includes receiving unit 802, determining unit 804,and communication unit 806. Receiving unit 802 may be configured toperform the receiving functions of apparatus 800. For example, receivingunit 802 may be configured to obtain one or more radio link monitoringconfigurations, each radio link monitoring configuration associated withat least one bandwidth part. In certain embodiments, receiving unit 802may be configured to receive the one or more radio link monitoringconfigurations in a message from a network node.

As another example, in certain embodiments a plurality of radio linkmonitoring configurations may be associated with the target bandwidthpart, and receiving unit 802 may be configured to receive an instructionvia downlink control information to use one of the plurality of radiolink monitoring configurations to perform radio link monitoring on thetarget bandwidth part.

Receiving unit 802 may receive any suitable information (e.g., from awireless device or another network node). Receiving unit 802 may includea receiver and/or a transceiver, such as RF transceiver circuitry 122described above in relation to FIG. 6. Receiving unit 802 may includecircuitry configured to receive messages and/or signals (wireless orwired). In particular embodiments, receiving unit 802 may communicatereceived messages and/or signals to determining unit 804 and/or anyother suitable unit of apparatus 800. The functions of receiving unit802 may, in certain embodiments, be performed in one or more distinctunits.

Determining unit 804 may perform the processing functions of apparatus800. For example, determining unit 804 may be configured to obtain oneor more radio link monitoring configurations, each radio link monitoringconfiguration associated with at least one bandwidth part. In certainembodiments, determining unit 804 may be configured to determine the oneor more radio link monitoring configurations according to one or morepre-defined rules. As another example, determining unit 804 may beconfigured to determine that the UE is to switch from a source bandwidthpart to a target bandwidth part.

As still another example, determining unit 804 may be configured toperform radio link monitoring on the target bandwidth part according toan obtained radio link monitoring configuration associated with thetarget bandwidth part. In certain embodiments, determining unit 804 maybe configured to perform monitoring of a downlink channel quality of afirst bandwidth part and a second bandwidth part. In certainembodiments, determining unit 804 may be configured to estimate, duringa first period of time, a radio link quality of the first bandwidth partaccording to a radio link monitoring configuration associated with thefirst bandwidth part; and estimate, during a second period of time, aradio link quality of the second bandwidth part according to a radiolink monitoring configuration associated with the second bandwidth part,wherein the second period of time at least partially overlaps with thefirst period of time.

As yet another example, in certain embodiments the radio link monitoringconfiguration associated with the target bandwidth part may comprise aplurality of sets of radio resources, and determining unit 804 may beconfigured to select one or more of the plurality of sets of radioresources to use to perform radio link monitoring on the targetbandwidth part based on a pre-defined rule.

As another example, in certain embodiments a radio link monitoringconfiguration associated with the source bandwidth part and the radiolink monitoring configuration associated with the target bandwidth partmay use the same radio resources, and determining unit 804 may beconfigured to use one or more of previously-performed measurements andpreviously-performed measurement samples to generate out-of-sync andin-sync events.

As another example, in certain embodiments a radio link monitoringconfiguration associated with the source bandwidth part and the radiolink monitoring configuration associated with the target bandwidth partmay use different radio resources, and to perform radio link monitoringon the target bandwidth part according to the obtained radio linkmonitoring configuration associated with the target bandwidth part,determining unit 804 may be configured to apply a relation function toone or more of previously-performed measurements andpreviously-performed measurement samples to generate out-of-sync andin-sync events without resetting a radio link failure timer or a radiolink failure counter. In certain embodiments, determining unit 804 maybe configured to reset at least one of a radio link failure timer and aradio link failure counter. In certain embodiments, determining unit 804may be configured to reset a set of radio link failure timers and radiolink failure counters associated with radio link monitoring forout-of-synch events and allow a set of radio link failure timers andradio link failure counters associated with radio link monitoring forin-synch events to continue. In certain embodiments, determining unit804 may be configured to reset one or more radio link failure timerswithout resetting any radio link failure counters.

Determining unit 804 may include or be included in one or moreprocessors, such as processing circuitry 120 described above in relationto FIG. 6. Determining unit 804 may include analog and/or digitalcircuitry configured to perform any of the functions of determining unit804 and/or processing circuitry 120 described above. The functions ofdetermining unit 804 may, in certain embodiments, be performed in one ormore distinct units.

Communication unit 806 may be configured to perform the transmissionfunctions of apparatus 800. Communication unit 806 may transmit messages(e.g., to a wireless device and/or another network node). Communicationunit 806 may include a transmitter and/or a transceiver, such as RFtransceiver circuitry 122 described above in relation to FIG. 6.Communication unit 806 may include circuitry configured to transmitmessages and/or signals (e.g., through wireless or wired means). Inparticular embodiments, communication unit 806 may receive messagesand/or signals for transmission from determining unit 804 or any otherunit of apparatus 800. The functions of communication unit 804 may, incertain embodiments, be performed in one or more distinct units.

The term unit may have conventional meaning in the field of electronics,electrical devices and/or electronic devices and may include, forexample, electrical and/or electronic circuitry, devices, modules,processors, memories, logic solid state and/or discrete devices,computer programs or instructions for carrying out respective tasks,procedures, computations, outputs, and/or displaying functions, and soon, as such as those that are described herein.

FIG. 9 is a flowchart of a method 900 in a network node, in accordancewith certain embodiments. Method 900 begins at step 901, where thenetwork node determines one or more radio link monitoringconfigurations, each radio link monitoring configuration associated withat least one bandwidth part.

In certain embodiments, each radio link monitoring configuration maycomprise a set of radio resources for performing radio link monitoringwithin its associated bandwidth part and one or more configurationparameters for performing radio link monitoring within its associatedbandwidth part. In certain embodiments, the set of radio resources maycomprise a CSI-RS resource. In certain embodiments, the set of radioresources may comprise a SSB.

In certain embodiments, the one or more configuration parameters forperforming radio link monitoring within its associated bandwidth partcomprise one or more of: one or more filtering parameters; one or moreradio link failure timers; an evaluation period; a number ofretransmissions before radio link failure is declared; a hypotheticalchannel configuration; a hypothetical signal configuration; and amapping function for a measured link quality and a hypothetical channelblock error rate. In certain embodiments, the one or more configurationparameters for performing radio link monitoring within its associatedbandwidth part may comprise one or more filtering parameters and the oneor more filtering parameters may comprise one or more of N310, N311, andN313, N314 counters. In certain embodiments, the one or moreconfiguration parameters for performing radio link monitoring within itsassociated bandwidth part may comprise one or more radio link failuretimers and the one or more radio link failure timers may comprise one ormore of T310, T311, T313, and T314 timers.

In certain embodiments, at least one of the determined one or more radiolink monitoring configurations may comprise a default radio linkmonitoring configuration. In certain embodiments, the default radio linkmonitoring configuration may be associated with a default bandwidthpart.

At step 902, the network node configures a UE to perform radio linkmonitoring on a target bandwidth part according to a radio linkmonitoring configuration associated with the target bandwidth part.

In certain embodiments, configuring the UE to perform radio linkmonitoring on the target bandwidth part according to the radio linkmonitoring configuration associated with the target bandwidth part maycomprise sending an indication of the radio link monitoringconfiguration associated with the target bandwidth part to the UE. Incertain embodiments, sending the indication of the radio link monitoringconfiguration associated with the target bandwidth part to the UE maycomprise sending an indication of the radio link monitoringconfiguration associated with the target bandwidth part in aninformation element within a bandwidth part configuration for the targetbandwidth part. In certain embodiments, sending the indication of theradio link monitoring configuration associated with the target bandwidthpart to the UE may comprise sending an indication of the radio linkmonitoring configuration associated with the target bandwidth part in aninformation element within a serving cell configuration. In certainembodiments, the indication may comprise a radio link monitoringconfiguration identifier.

In certain embodiments, configuring the UE to perform radio linkmonitoring on the target bandwidth part according to the radio linkmonitoring configuration associated with the target bandwidth part maycomprise configuring the UE to determine the radio link monitoringconfiguration associated with the target bandwidth part according to oneor more predefined rules.

In certain embodiments, the radio link monitoring configurationassociated with the target bandwidth part may comprise a plurality ofsets of radio resources, and the method may further comprise configuringthe UE to select one or more of the plurality of sets of radio resourcesto use to perform radio link monitoring on the target bandwidth partbased on a pre-defined rule.

In certain embodiments, a plurality of radio link monitoringconfigurations may be associated with the target bandwidth part, and themethod may further comprise sending an instruction to the UE to use oneof the plurality of radio link monitoring configurations to performradio link monitoring on the target bandwidth part.

In certain embodiments, a radio link monitoring configuration associatedwith a source bandwidth part and the radio link monitoring configurationassociated with the target bandwidth part may use the same radioresources, and configuring the UE to perform radio link monitoring onthe target bandwidth part according to the radio link monitoringconfiguration associated with the target bandwidth part may compriseconfiguring the UE to use one or more of previously-performedmeasurements and previously-performed measurement samples to generateout-of-sync and in-sync events.

In certain embodiments, a radio link monitoring configuration associatedwith a source bandwidth part and the radio link monitoring configurationassociated with the target bandwidth part may use different radioresources. In certain embodiments, configuring the UE to perform radiolink monitoring on the target bandwidth part according to the radio linkmonitoring configuration associated with the target bandwidth part maycomprise configuring the UE to apply a relation function to one or morepreviously-performed measurements and previously-performed measurementsamples to generate out-of-sync and in-sync events without resetting aradio link failure timer or a radio link failure counter. In certainembodiments, configuring the UE to perform radio link monitoring on thetarget bandwidth part according to the radio link monitoringconfiguration associated with the target bandwidth part may compriseconfiguring the UE to reset at least one of a radio link failure timerand a radio link failure counter. In certain embodiments, configuringthe UE to reset at least one of a radio link failure timer and a radiolink failure counter may comprise configuring the UE to reset a set ofradio link failure timers and radio link failure counters associatedwith radio link monitoring for out-of-synch events and configuring theUE to allow a set of radio link failure timers and radio link failurecounters associated with radio link monitoring for in-synch measurementsto continue. In certain embodiments, configuring the UE to reset atleast one of a radio link failure timer and a radio link failure countermay comprise configuring the UE to reset one or more radio link failuretimers without resetting any radio link failure counters.

FIG. 10 is a schematic block diagram of a virtualization apparatus, inaccordance with certain embodiments. More particularly, FIG. 10illustrates a schematic block diagram of an apparatus 1000 in a wirelessnetwork (for example, the wireless network shown in FIG. 6). Theapparatus may be implemented in a network node (e.g., network node 160shown in FIG. 6). Apparatus 1000 is operable to carry out the examplemethod described with reference to FIG. 9 and possibly any otherprocesses or methods disclosed herein. It is also to be understood thatthe method of FIG. 9 is not necessarily carried out solely by apparatus1000. At least some operations of the method can be performed by one ormore other entities.

Virtual Apparatus 1000 may comprise processing circuitry, which mayinclude one or more microprocessor or microcontrollers, as well as otherdigital hardware, which may include digital signal processors (DSPs),special-purpose digital logic, and the like. The processing circuitrymay be configured to execute program code stored in memory, which mayinclude one or several types of memory such as read-only memory (ROM),random-access memory, cache memory, flash memory devices, opticalstorage devices, etc. Program code stored in memory includes programinstructions for executing one or more telecommunications and/or datacommunications protocols as well as instructions for carrying out one ormore of the techniques described herein, in several embodiments. In someimplementations, the processing circuitry may be used to cause receivingunit 1002, determining unit 1004, communication unit 1006, and any othersuitable units of apparatus 1000 to perform corresponding functionsaccording one or more embodiments of the present disclosure.

In certain embodiments, apparatus 1000 may be an eNB or a gNB. Asillustrated in FIG. 10, apparatus 1000 includes receiving unit 1002,determining unit 1004, and communication unit 1006. Receiving unit 1002may be configured to perform the receiving functions of apparatus 1000.Receiving unit 1002 may receive any suitable information (e.g., from awireless device or another network node). Receiving unit 1002 mayinclude a receiver and/or a transceiver, such as RF transceivercircuitry 172 described above in relation to FIG. 6. Receiving unit 1002may include circuitry configured to receive messages and/or signals(wireless or wired). In particular embodiments, receiving unit 1002 maycommunicate received messages and/or signals to determining unit 1004and/or any other suitable unit of apparatus 1000. The functions ofreceiving unit 1002 may, in certain embodiments, be performed in one ormore distinct units.

Determining unit 1004 may perform the processing functions of apparatus1000. For example, determining unit 1004 may be configured to determineone or more radio link monitoring configurations, each radio linkmonitoring configuration associated with at least one bandwidth part. Asanother example, determining unit 1004 may be configured to configure aUE to perform radio link monitoring on a target bandwidth part accordingto a radio link monitoring configuration associated with the targetbandwidth part. In certain embodiments, determining unit 1004 may beconfigured to configure the UE to determine the radio link monitoringconfiguration associated with the target bandwidth part according to oneor more predefined rules. In certain embodiments, the radio linkmonitoring configuration associated with the target bandwidth part maycomprise a plurality of sets of radio resources, and determining unit1004 may be configured to configure the UE to select one or more of theplurality of sets of radio resources to use to perform radio linkmonitoring on the target bandwidth part based on a pre-defined rule. Incertain embodiments, a radio link monitoring configuration associatedwith a source bandwidth part and the radio link monitoring configurationassociated with the target bandwidth part may use the same radioresources, and determining unit 1004 may be configured to configure theUE to use one or more of previously-performed measurements andpreviously-performed measurement samples to generate out-of-sync andin-sync events. In certain embodiments, a radio link monitoringconfiguration associated with a source bandwidth part and the radio linkmonitoring configuration associated with the target bandwidth part mayuse different radio resources, and determining unit 1004 may beconfigured to configure the UE to apply a relation function to one ormore previously-performed measurements and previously-performedmeasurement samples to generate out-of-sync and in-sync events withoutresetting a radio link failure timer or a radio link failure counter. Incertain embodiments, determining unit 1004 may be configured toconfigure the UE to reset at least one of a radio link failure timer anda radio link failure counter. In certain embodiments, determining unit1004 may be configured to configure the UE to reset a set of radio linkfailure timers and radio link failure counters associated with radiolink monitoring for out-of-synch events and configure the UE to allow aset of radio link failure timers and radio link failure countersassociated with radio link monitoring for in-synch measurements tocontinue. In certain embodiments, determining unit 1004 may beconfigured to configure the UE to reset one or more radio link failuretimers without resetting any radio link failure counters.

Determining unit 1004 may include or be included in one or moreprocessors, such as processing circuitry 170 described above in relationto FIG. 6. Determining unit 1004 may include analog and/or digitalcircuitry configured to perform any of the functions of determining unit1004 and/or processing circuitry 170 described above. The functions ofdetermining unit 1004 may, in certain embodiments, be performed in oneor more distinct units.

Communication unit 1006 may be configured to perform the transmissionfunctions of apparatus 1000. For example, in certain embodiments aplurality of radio link monitoring configurations may be associated withthe target bandwidth part, and communication unit 1006 may be configuredto send an instruction to the UE to use one of the plurality of radiolink monitoring configurations to perform radio link monitoring on thetarget bandwidth part. As another example, communication unit 1006 maybe configured to send an indication of the radio link monitoringconfiguration associated with the target bandwidth part to the UE. Incertain embodiments, communication unit 1006 may be configured to sendan indication of the radio link monitoring configuration associated withthe target bandwidth part in an information element within a bandwidthpart configuration for the target bandwidth part. In certainembodiments, communication unit 1006 may be configured to send anindication of the radio link monitoring configuration associated withthe target bandwidth part in an information element within a servingcell configuration.

Communication unit 1006 may transmit messages (e.g., to a wirelessdevice and/or another network node). Communication unit 1006 may includea transmitter and/or a transceiver, such as RF transceiver circuitry 172described above in relation to FIG. 6 Communication unit 1006 mayinclude circuitry configured to transmit messages and/or signals (e.g.,through wireless or wired means). In particular embodiments,communication unit 1006 may receive messages and/or signals fortransmission from determining unit 1004 or any other unit of apparatus1000. The functions of communication unit 1004 may, in certainembodiments, be performed in one or more distinct units.

The term unit may have conventional meaning in the field of electronics,electrical devices and/or electronic devices and may include, forexample, electrical and/or electronic circuitry, devices, modules,processors, memories, logic solid state and/or discrete devices,computer programs or instructions for carrying out respective tasks,procedures, computations, outputs, and/or displaying functions, and soon, as such as those that are described herein.

FIG. 11 illustrates one embodiment of a UE, in accordance with certainembodiments. As used herein, a user equipment or UE may not necessarilyhave a user in the sense of a human user who owns and/or operates therelevant device. Instead, a UE may represent a device that is intendedfor sale to, or operation by, a human user but which may not, or whichmay not initially, be associated with a specific human user. A UE mayalso comprise any UE identified by the 3rd Generation PartnershipProject (3GPP), including a NB-IoT UE that is not intended for sale to,or operation by, a human user. UE 1100, as illustrated in FIG. 11, isone example of a WD configured for communication in accordance with oneor more communication standards promulgated by the 3rd GenerationPartnership Project (3GPP), such as 3GPP's GSM, UMTS, LTE, and/or 5Gstandards. As mentioned previously, the term WD and UE may be usedinterchangeable. Accordingly, although FIG. 11 is a UE, the componentsdiscussed herein are equally applicable to a WD, and vice-versa.

In FIG. 11, UE 1100 includes processing circuitry 1101 that isoperatively coupled to input/output interface 1105, radio frequency (RF)interface 1109, network connection interface 1111, memory 1115 includingrandom access memory (RAM) 1117, read-only memory (ROM) 1119, andstorage medium 1121 or the like, communication subsystem 1131, powersource 1113, and/or any other component, or any combination thereof.Storage medium 1121 includes operating system 1123, application program1125, and data 1127. In other embodiments, storage medium 1121 mayinclude other similar types of information. Certain UEs may utilize allof the components shown in FIG. 11, or only a subset of the components.The level of integration between the components may vary from one UE toanother UE. Further, certain UEs may contain multiple instances of acomponent, such as multiple processors, memories, transceivers,transmitters, receivers, etc.

In FIG. 11, processing circuitry 1101 may be configured to processcomputer instructions and data. Processing circuitry 1101 may beconfigured to implement any sequential state machine operative toexecute machine instructions stored as machine-readable computerprograms in the memory, such as one or more hardware-implemented statemachines (e.g., in discrete logic, FPGA, ASIC, etc.); programmable logictogether with appropriate firmware; one or more stored program,general-purpose processors, such as a microprocessor or Digital SignalProcessor (DSP), together with appropriate software; or any combinationof the above. For example, the processing circuitry 1101 may include twocentral processing units (CPUs). Data may be information in a formsuitable for use by a computer.

In the depicted embodiment, input/output interface 1105 may beconfigured to provide a communication interface to an input device,output device, or input and output device. UE 1100 may be configured touse an output device via input/output interface 1105. An output devicemay use the same type of interface port as an input device. For example,a USB port may be used to provide input to and output from UE 1100. Theoutput device may be a speaker, a sound card, a video card, a display, amonitor, a printer, an actuator, an emitter, a smartcard, another outputdevice, or any combination thereof. UE 1100 may be configured to use aninput device via input/output interface 1105 to allow a user to captureinformation into UE 1100. The input device may include a touch-sensitiveor presence-sensitive display, a camera (e.g., a digital camera, adigital video camera, a web camera, etc.), a microphone, a sensor, amouse, a trackball, a directional pad, a trackpad, a scroll wheel, asmartcard, and the like. The presence-sensitive display may include acapacitive or resistive touch sensor to sense input from a user. Asensor may be, for instance, an accelerometer, a gyroscope, a tiltsensor, a force sensor, a magnetometer, an optical sensor, a proximitysensor, another like sensor, or any combination thereof. For example,the input device may be an accelerometer, a magnetometer, a digitalcamera, a microphone, and an optical sensor.

In FIG. 11, RF interface 1109 may be configured to provide acommunication interface to RF components such as a transmitter, areceiver, and an antenna. Network connection interface 1111 may beconfigured to provide a communication interface to network 1143 a.Network 1143 a may encompass wired and/or wireless networks such as alocal-area network (LAN), a wide-area network (WAN), a computer network,a wireless network, a telecommunications network, another like networkor any combination thereof. For example, network 1143 a may comprise aWi-Fi network. Network connection interface 1111 may be configured toinclude a receiver and a transmitter interface used to communicate withone or more other devices over a communication network according to oneor more communication protocols, such as Ethernet, TCP/IP, SONET, ATM,or the like. Network connection interface 1111 may implement receiverand transmitter functionality appropriate to the communication networklinks (e.g., optical, electrical, and the like). The transmitter andreceiver functions may share circuit components, software or firmware,or alternatively may be implemented separately.

RAM 1117 may be configured to interface via bus 1102 to processingcircuitry 1101 to provide storage or caching of data or computerinstructions during the execution of software programs such as theoperating system, application programs, and device drivers. ROM 1119 maybe configured to provide computer instructions or data to processingcircuitry 1101. For example, ROM 1119 may be configured to storeinvariant low-level system code or data for basic system functions suchas basic input and output (I/O), startup, or reception of keystrokesfrom a keyboard that are stored in a non-volatile memory. Storage medium1121 may be configured to include memory such as RAM, ROM, programmableread-only memory (PROM), erasable programmable read-only memory (EPROM),electrically erasable programmable read-only memory (EEPROM), magneticdisks, optical disks, floppy disks, hard disks, removable cartridges, orflash drives. In one example, storage medium 1121 may be configured toinclude operating system 1123, application program 1125 such as a webbrowser application, a widget or gadget engine or another application,and data file 1127. Storage medium 1121 may store, for use by UE 1100,any of a variety of various operating systems or combinations ofoperating systems.

Storage medium 1121 may be configured to include a number of physicaldrive units, such as redundant array of independent disks (RAID), floppydisk drive, flash memory, USB flash drive, external hard disk drive,thumb drive, pen drive, key drive, high-density digital versatile disc(HD-DVD) optical disc drive, internal hard disk drive, Btu-Ray opticaldisc drive, holographic digital data storage (HDDS) optical disc drive,external mini-dual in-line memory module (DIMM), synchronous dynamicrandom access memory (SDRAM), external micro-DIMM SDRAM, smartcardmemory such as a subscriber identity module or a removable user identity(SIM/RUIM) module, other memory, or any combination thereof. Storagemedium 1121 may allow UE 1100 to access computer-executableinstructions, application programs or the like, stored on transitory ornon-transitory memory media, to off-load data, or to upload data. Anarticle of manufacture, such as one utilizing a communication system maybe tangibly embodied in storage medium 1121, which may comprise a devicereadable medium.

In FIG. 11, processing circuitry 1101 may be configured to communicatewith network 1143 b using communication subsystem 1131. Network 1143 aand network 1143 b may be the same network or networks or differentnetwork or networks. Communication subsystem 1131 may be configured toinclude one or more transceivers used to communicate with network 1143b. For example, communication subsystem 1131 may be configured toinclude one or more transceivers used to communicate with one or moreremote transceivers of another device capable of wireless communicationsuch as another WD, UE, or base station of a radio access network (RAN)according to one or more communication protocols, such as IEEE 802.QQ2,CDMA, WCDMA, GSM, LTE, UTRAN, WiMax, or the like. Each transceiver mayinclude transmitter 1133 and/or receiver 1135 to implement transmitteror receiver functionality, respectively, appropriate to the RAN links(e.g., frequency allocations and the like). Further, transmitter 1133and receiver 1135 of each transceiver may share circuit components,software or firmware, or alternatively may be implemented separately.

In the illustrated embodiment, the communication functions ofcommunication subsystem 1131 may include data communication, voicecommunication, multimedia communication, short-range communications suchas Bluetooth, near-field communication, location-based communicationsuch as the use of the global positioning system (GPS) to determine alocation, another like communication function, or any combinationthereof. For example, communication subsystem 1131 may include cellularcommunication, Wi-Fi communication, Bluetooth communication, and GPScommunication. Network 1143 b may encompass wired and/or wirelessnetworks such as a local-area network (LAN), a wide-area network (WAN),a computer network, a wireless network, a telecommunications network,another like network or any combination thereof. For example, network1143 b may be a cellular network, a Wi-Fi network, and/or a near-fieldnetwork. Power source 1113 may be configured to provide alternatingcurrent (AC) or direct current (DC) power to components of UE 1100.

The features, benefits and/or functions described herein may beimplemented in one of the components of UE 1100 or partitioned acrossmultiple components of UE 1100. Further, the features, benefits, and/orfunctions described herein may be implemented in any combination ofhardware, software or firmware. In one example, communication subsystem1131 may be configured to include any of the components describedherein. Further, processing circuitry 1101 may be configured tocommunicate with any of such components over bus 1102. In anotherexample, any of such components may be represented by programinstructions stored in memory that when executed by processing circuitry1101 perform the corresponding functions described herein. In anotherexample, the functionality of any of such components may be partitionedbetween processing circuitry 1101 and communication subsystem 1131. Inanother example, the non-computationally intensive functions of any ofsuch components may be implemented in software or firmware and thecomputationally intensive functions may be implemented in hardware.

FIG. 12 is a schematic block diagram illustrating a virtualizationenvironment, in accordance with certain embodiments. More particularly,FIG. 12 is a schematic block diagram illustrating a virtualizationenvironment 1200 in which functions implemented by some embodiments maybe virtualized. In the present context, virtualizing means creatingvirtual versions of apparatuses or devices which may includevirtualizing hardware platforms, storage devices and networkingresources. As used herein, virtualization can be applied to a node(e.g., a virtualized base station or a virtualized radio access node) orto a device (e.g., a UE, a wireless device or any other type ofcommunication device) or components thereof and relates to animplementation in which at least a portion of the functionality isimplemented as one or more virtual components (e.g., via one or moreapplications, components, functions, virtual machines or containersexecuting on one or more physical processing nodes in one or morenetworks).

In some embodiments, some or all of the functions described herein maybe implemented as virtual components executed by one or more virtualmachines implemented in one or more virtual environments 1200 hosted byone or more of hardware nodes 1230. Further, in embodiments in which thevirtual node is not a radio access node or does not require radioconnectivity (e.g., a core network node), then the network node may beentirely virtualized. The functions may be implemented by one or moreapplications 1220 (which may alternatively be called software instances,virtual appliances, network functions, virtual nodes, virtual networkfunctions, etc.) operative to implement some of the features, functions,and/or benefits of some of the embodiments disclosed herein.Applications 1220 are run in virtualization environment 1200 whichprovides hardware 1230 comprising processing circuitry 1260 and memory1290. Memory 1290 contains instructions 1295 executable by processingcircuitry 1260 whereby application 1220 is operative to provide one ormore of the features, benefits, and/or functions disclosed herein.

Virtualization environment 1200, comprises general-purpose orspecial-purpose network hardware devices 1230 comprising a set of one ormore processors or processing circuitry 1260, which may be commercialoff-the-shelf (COTS) processors, dedicated Application SpecificIntegrated Circuits (ASICs), or any other type of processing circuitryincluding digital or analog hardware components or special purposeprocessors. Each hardware device may comprise memory 1290-1 which may benon-persistent memory for temporarily storing instructions 1295 orsoftware executed by processing circuitry 1260. Each hardware device maycomprise one or more network interface controllers (NICs) 1270, alsoknown as network interface cards, which include physical networkinterface 1280. Each hardware device may also include non-transitory,persistent, machine-readable storage media 1290-2 having stored thereinsoftware 1295 and/or instructions executable by processing circuitry1260. Software 1295 may include any type of software including softwarefor instantiating one or more virtualization layers 1250 (also referredto as hypervisors), software to execute virtual machines 1240 as well assoftware allowing it to execute functions, features and/or benefitsdescribed in relation with some embodiments described herein.

Virtual machines 1240, comprise virtual processing, virtual memory,virtual networking or interface and virtual storage, and may be run by acorresponding virtualization layer 1250 or hypervisor. Differentembodiments of the instance of virtual appliance 1220 may be implementedon one or more of virtual machines 1240, and the implementations may bemade in different ways.

During operation, processing circuitry 1260 executes software 1295 toinstantiate the hypervisor or virtualization layer 1250, which maysometimes be referred to as a virtual machine monitor (VMM).Virtualization layer 1250 may present a virtual operating platform thatappears like networking hardware to virtual machine 1240.

As shown in FIG. 12, hardware 1230 may be a standalone network node withgeneric or specific components. Hardware 1230 may comprise antenna 12225and may implement some functions via virtualization. Alternatively,hardware 1230 may be part of a larger cluster of hardware (e.g. such asin a data center or customer premise equipment (CPE)) where manyhardware nodes work together and are managed via management andorchestration (MANO) 12100, which, among others, oversees lifecyclemanagement of applications 1220.

Virtualization of the hardware is in some contexts referred to asnetwork function virtualization (NFV). NFV may be used to consolidatemany network equipment types onto industry standard high-volume serverhardware, physical switches, and physical storage, which can be locatedin data centers, and customer premise equipment.

In the context of NFV, virtual machine 1240 may be a softwareimplementation of a physical machine that runs programs as if they wereexecuting on a physical, non-virtualized machine. Each of virtualmachines 1240, and that part of hardware 1230 that executes that virtualmachine, be it hardware dedicated to that virtual machine and/orhardware shared by that virtual machine with others of the virtualmachines 1240, forms a separate virtual network elements (VNE).

Still in the context of NFV, Virtual Network Function (VNF) isresponsible for handling specific network functions that run in one ormore virtual machines 1240 on top of hardware networking infrastructure1230 and corresponds to application 1220 in FIG. 12.

In some embodiments, one or more radio units 12200 that each include oneor more transmitters 12220 and one or more receivers 12210 may becoupled to one or more antennas 12225. Radio units 12200 may communicatedirectly with hardware nodes 1230 via one or more appropriate networkinterfaces and may be used in combination with the virtual components toprovide a virtual node with radio capabilities, such as a radio accessnode or a base station.

In some embodiments, some signalling can be effected with the use ofcontrol system 12230 which may alternatively be used for communicationbetween the hardware nodes 1230 and radio units 12200.

FIG. 13 illustrates an example telecommunication network connected viaan intermediate network to a host computer, in accordance with certainembodiments. With reference to FIG. 13, in accordance with anembodiment, a communication system includes telecommunication network1310, such as a 3GPP-type cellular network, which comprises accessnetwork 1311, such as a radio access network, and core network 1314.Access network 1311 comprises a plurality of base stations 1312 a, 1312b, 1312 c, such as NBs, eNBs, gNBs or other types of wireless accesspoints, each defining a corresponding coverage area 1313 a, 1313 b, 1313c. Each base station 1312 a, 1312 b, 1312 c is connectable to corenetwork 1314 over a wired or wireless connection 1315. A first UE 1391located in coverage area 1313 c is configured to wirelessly connect to,or be paged by, the corresponding base station 1312 c. A second UE 1392in coverage area 1313 a is wirelessly connectable to the correspondingbase station 1312 a. While a plurality of UEs 1391, 1392 are illustratedin this example, the disclosed embodiments are equally applicable to asituation where a sole UE is in the coverage area or where a sole UE isconnecting to the corresponding base station 1312.

Telecommunication network 1310 is itself connected to host computer1330, which may be embodied in the hardware and/or software of astandalone server, a cloud-implemented server, a distributed server oras processing resources in a server farm. Host computer 1330 may beunder the ownership or control of a service provider, or may be operatedby the service provider or on behalf of the service provider.Connections 1321 and 1322 between telecommunication network 1310 andhost computer 1330 may extend directly from core network 1314 to hostcomputer 1330 or may go via an optional intermediate network 1320.Intermediate network 1320 may be one of, or a combination of more thanone of, a public, private or hosted network; intermediate network 1320,if any, may be a backbone network or the Internet; in particular,intermediate network 1320 may comprise two or more sub-networks (notshown).

The communication system of FIG. 13 as a whole enables connectivitybetween the connected UEs 1391, 1392 and host computer 1330. Theconnectivity may be described as an over-the-top (OTT) connection 1350.Host computer 1330 and the connected UEs 1391, 1392 are configured tocommunicate data and/or signaling via OTT connection 1350, using accessnetwork 1311, core network 1314, any intermediate network 1320 andpossible further infrastructure (not shown) as intermediaries. OTTconnection 1350 may be transparent in the sense that the participatingcommunication devices through which OTT connection 1350 passes areunaware of routing of UL and DL communications. For example, basestation 1312 may not or need not be informed about the past routing ofan incoming downlink communication with data originating from hostcomputer 1330 to be forwarded (e.g., handed over) to a connected UE1391. Similarly, base station 1312 need not be aware of the futurerouting of an outgoing UL communication originating from the UE 1391towards the host computer 1330.

FIG. 14 illustrates an example of a host computer communicating via abase station with a UE over a partially wireless connection, inaccordance with certain embodiments. Example implementations, inaccordance with an embodiment, of the UE, base station and host computerdiscussed in the preceding paragraphs will now be described withreference to FIG. 14. In communication system 1400, host computer 1410comprises hardware 1415 including communication interface 1416configured to set up and maintain a wired or wireless connection with aninterface of a different communication device of communication system1400. Host computer 1410 further comprises processing circuitry 1418,which may have storage and/or processing capabilities. In particular,processing circuitry 1418 may comprise one or more programmableprocessors, application-specific integrated circuits, field programmablegate arrays or combinations of these (not shown) adapted to executeinstructions. Host computer 1410 further comprises software 1411, whichis stored in or accessible by host computer 1410 and executable byprocessing circuitry 1418. Software 1411 includes host application 1412.Host application 1412 may be operable to provide a service to a remoteuser, such as UE 1430 connecting via OTT connection 1450 terminating atUE 1430 and host computer 1410. In providing the service to the remoteuser, host application 1412 may provide user data which is transmittedusing OTT connection 1450.

Communication system 1400 further includes base station 1420 provided ina telecommunication system and comprising hardware 1425 enabling it tocommunicate with host computer 1410 and with UE 1430. Hardware 1425 mayinclude communication interface 1426 for setting up and maintaining awired or wireless connection with an interface of a differentcommunication device of communication system 1400, as well as radiointerface 1427 for setting up and maintaining at least wirelessconnection 1470 with UE 1430 located in a coverage area (not shown inFIG. 14) served by base station 1420. Communication interface 1426 maybe configured to facilitate connection 1460 to host computer 1410.Connection 1460 may be direct, or it may pass through a core network(not explicitly shown in FIG. 14) of the telecommunication system and/orthrough one or more intermediate networks outside the telecommunicationsystem. In the embodiment shown, hardware 1425 of base station 1420further includes processing circuitry 1428, which may comprise one ormore programmable processors, application-specific integrated circuits,field programmable gate arrays or combinations of these (not shown)adapted to execute instructions. Base station 1420 further has software1421 stored internally or accessible via an external connection.

Communication system 1400 further includes UE 1430 already referred to.Its hardware 1435 may include radio interface 1437 configured to set upand maintain wireless connection 1470 with a base station serving acoverage area in which UE 1430 is currently located. Hardware 1435 of UE1430 further includes processing circuitry 1438, which may comprise oneor more programmable processors, application-specific integratedcircuits, field programmable gate arrays or combinations of these (notshown) adapted to execute instructions. UE 1430 further comprisessoftware 1431, which is stored in or accessible by UE 1430 andexecutable by processing circuitry 1438. Software 1431 includes clientapplication 1432. Client application 1432 may be operable to provide aservice to a human or non-human user via UE 1430, with the support ofhost computer 1410. In host computer 1410, an executing host application1412 may communicate with the executing client application 1432 via OTTconnection 1450 terminating at UE 1430 and host computer 1410. Inproviding the service to the user, client application 1432 may receiverequest data from host application 1412 and provide user data inresponse to the request data. OTT connection 1450 may transfer both therequest data and the user data. Client application 1432 may interactwith the user to generate the user data that it provides.

It is noted that host computer 1410, base station 1420 and UE 1430illustrated in FIG. 14 may be similar or identical to host computer1330, one of base stations 1312 a, 1312 b, 1312 c and one of UEs 1391,1392 of FIG. 13, respectively. This is to say, the inner workings ofthese entities may be as shown in FIG. 14 and independently, thesurrounding network topology may be that of FIG. 13.

In FIG. 14, OTT connection 1450 has been drawn abstractly to illustratethe communication between host computer 1410 and UE 1430 via basestation 1420, without explicit reference to any intermediary devices andthe precise routing of messages via these devices. Networkinfrastructure may determine the routing, which it may be configured tohide from UE 1430 or from the service provider operating host computer1410, or both. While OTT connection 1450 is active, the networkinfrastructure may further take decisions by which it dynamicallychanges the routing (e.g., on the basis of load balancing considerationor reconfiguration of the network).

Wireless connection 1470 between UE 1430 and base station 1420 is inaccordance with the teachings of the embodiments described throughoutthis disclosure. One or more of the various embodiments improve theperformance of OTT services provided to UE 1430 using OTT connection1450, in which wireless connection 1470 forms the last segment. Moreprecisely, the teachings of these embodiments may improve the powerconsumption and thereby provide benefits such as extended batterylifetime and reduced user waiting time.

A measurement procedure may be provided for the purpose of monitoringdata rate, latency and other factors on which the one or moreembodiments improve. There may further be an optional networkfunctionality for reconfiguring OTT connection 1450 between hostcomputer 1410 and UE 1430, in response to variations in the measurementresults. The measurement procedure and/or the network functionality forreconfiguring OTT connection 1450 may be implemented in software 1411and hardware 1415 of host computer 1410 or in software 1431 and hardware1435 of UE 1430, or both. In embodiments, sensors (not shown) may bedeployed in or in association with communication devices through whichOTT connection 1450 passes; the sensors may participate in themeasurement procedure by supplying values of the monitored quantitiesexemplified above, or supplying values of other physical quantities fromwhich software 1411, 1431 may compute or estimate the monitoredquantities. The reconfiguring of OTT connection 1450 may include messageformat, retransmission settings, preferred routing etc.; thereconfiguring need not affect base station 1420, and it may be unknownor imperceptible to base station 1420. Such procedures andfunctionalities may be known and practiced in the art. In certainembodiments, measurements may involve proprietary UE signalingfacilitating host computer 1410's measurements of throughput,propagation times, latency and the like. The measurements may beimplemented in that software 1411 and 1431 causes messages to betransmitted, in particular empty or ‘dummy’ messages, using OTTconnection 1450 while it monitors propagation times, errors etc.

FIG. 15 is a flowchart of a method implemented in a communicationsystem, in accordance with certain embodiments. The communication systemincludes a host computer, a base station and a UE which may be thosedescribed with reference to FIGS. 13 and 14. For simplicity of thepresent disclosure, only drawing references to FIG. 15 will be includedin this section. In step 1510, the host computer provides user data. Insubstep 1511 (which may be optional) of step 1510, the host computerprovides the user data by executing a host application. In step 1520,the host computer initiates a transmission carrying the user data to theUE. In step 1530 (which may be optional), the base station transmits tothe UE the user data which was carried in the transmission that the hostcomputer initiated, in accordance with the teachings of the embodimentsdescribed throughout this disclosure. In step 1540 (which may also beoptional), the UE executes a client application associated with the hostapplication executed by the host computer.

FIG. 16 is a flowchart of a method implemented in a communicationsystem, in accordance with certain embodiments. The communication systemincludes a host computer, a base station and a UE which may be thosedescribed with reference to FIGS. 13 and 14. For simplicity of thepresent disclosure, only drawing references to FIG. 16 will be includedin this section. In step 1610 of the method, the host computer providesuser data. In an optional substep (not shown) the host computer providesthe user data by executing a host application. In step 1620, the hostcomputer initiates a transmission carrying the user data to the UE. Thetransmission may pass via the base station, in accordance with theteachings of the embodiments described throughout this disclosure. Instep 1630 (which may be optional), the UE receives the user data carriedin the transmission.

FIG. 17 is a flowchart of a method implemented in a communicationsystem, in accordance with certain embodiments. The communication systemincludes a host computer, a base station and a UE which may be thosedescribed with reference to FIGS. 13 and 14. For simplicity of thepresent disclosure, only drawing references to FIG. 17 will be includedin this section. In step 1710 (which may be optional), the UE receivesinput data provided by the host computer. Additionally or alternatively,in step 1720, the UE provides user data. In substep 1721 (which may beoptional) of step 1720, the UE provides the user data by executing aclient application. In substep 1711 (which may be optional) of step1710, the UE executes a client application which provides the user datain reaction to the received input data provided by the host computer. Inproviding the user data, the executed client application may furtherconsider user input received from the user. Regardless of the specificmanner in which the user data was provided, the UE initiates, in substep1730 (which may be optional), transmission of the user data to the hostcomputer. In step 1740 of the method, the host computer receives theuser data transmitted from the UE, in accordance with the teachings ofthe embodiments described throughout this disclosure.

FIG. 18 is a flowchart of a method implemented in a communicationsystem, in accordance with certain embodiments. The communication systemincludes a host computer, a base station and a UE which may be thosedescribed with reference to FIGS. 13 and 14. For simplicity of thepresent disclosure, only drawing references to FIG. 18 will be includedin this section. In step 1810 (which may be optional), in accordancewith the teachings of the embodiments described throughout thisdisclosure, the base station receives user data from the UE. In step1820 (which may be optional), the base station initiates transmission ofthe received user data to the host computer. In step 1830 (which may beoptional), the host computer receives the user data carried in thetransmission initiated by the base station.

Any appropriate steps, methods, features, functions, or benefitsdisclosed herein may be performed through one or more functional unitsor modules of one or more virtual apparatuses. Each virtual apparatusmay comprise a number of these functional units. These functional unitsmay be implemented via processing circuitry, which may include one ormore microprocessor or microcontrollers, as well as other digitalhardware, which may include digital signal processors (DSPs),special-purpose digital logic, and the like. The processing circuitrymay be configured to execute program code stored in memory, which mayinclude one or several types of memory such as read-only memory (ROM),random-access memory (RAM), cache memory, flash memory devices, opticalstorage devices, etc. Program code stored in memory includes programinstructions for executing one or more telecommunications and/or datacommunications protocols as well as instructions for carrying out one ormore of the techniques described herein. In some implementations, theprocessing circuitry may be used to cause the respective functional unitto perform corresponding functions according one or more embodiments ofthe present disclosure.

Modifications, additions, or omissions may be made to the systems andapparatuses described herein without departing from the scope of thedisclosure. The components of the systems and apparatuses may beintegrated or separated. Moreover, the operations of the systems andapparatuses may be performed by more, fewer, or other components.Additionally, operations of the systems and apparatuses may be performedusing any suitable logic comprising software, hardware, and/or otherlogic. As used in this document, “each” refers to each member of a setor each member of a subset of a set.

Modifications, additions, or omissions may be made to the methodsdescribed herein without departing from the scope of the disclosure. Themethods may include more, fewer, or other steps. Additionally, steps maybe performed in any suitable order.

Although this disclosure has been described in terms of certainembodiments, alterations and permutations of the embodiments will beapparent to those skilled in the art. Accordingly, the above descriptionof the embodiments does not constrain this disclosure. Other changes,substitutions, and alterations are possible without departing from thespirit and scope of this disclosure, as defined by the following claims.

At least some of the following abbreviations may be used in thisdisclosure. If there is an inconsistency between abbreviations,preference should be given to how it is used above. If listed multipletimes below, the first listing should be preferred over any subsequentlisting(s).

-   -   1×RTT CDMA2000 1× Radio Transmission Technology    -   3GPP 3rd Generation Partnership Project    -   5G 5th Generation    -   ABS Almost Blank Subframe    -   ARQ Automatic Repeat Request    -   ASN.1 Abstract Syntax Notation One    -   AWGN Additive White Gaussian Noise    -   BCCH Broadcast Control Channel    -   BCH Broadcast Channel    -   BLER Block Error Rate    -   BWP Bandwidth Part    -   CA Carrier Aggregation    -   CC Carrier Component    -   CCCH SDU Common Control Channel SDU    -   CDMA Code Division Multiplexing Access    -   CGI Cell Global Identifier    -   CIR Channel Impulse Response    -   CORESET Control Resource Set    -   CP Cyclic Prefix    -   CPICH Common Pilot Channel    -   CPICH Ec/No CPICH Received energy per chip divided by the power        density in the band    -   CQI Channel Quality information    -   C-RNTI Cell RNTI    -   CRS Cell-specific Reference Signal    -   CSI Channel State Information    -   CSI-RS Channel State Information Reference Signal    -   DCCH Dedicated Control Channel    -   DCI Downlink Control Information    -   DL Downlink    -   DM Demodulation    -   DMRS Demodulation Reference Signal    -   DRB Data Radio Bearer    -   DRX Discontinuous Reception    -   DTX Discontinuous Transmission    -   DTCH Dedicated Traffic Channel    -   DUT Device Under Test    -   E-CID Enhanced Cell-ID (positioning method)    -   E-SMLC Evolved-Serving Mobile Location Centre    -   E-UTRAN Evolved Universal Terrestrial Radio Access Network    -   ECGI Evolved CGI    -   eNB E-UTRAN NodeB    -   ePDCCH enhanced Physical Downlink Control Channel    -   E-SMLC evolved Serving Mobile Location Center    -   E-UTRA Evolved UTRA    -   E-UTRAN Evolved UTRAN    -   FDD Frequency Division Duplex    -   FFS For Further Study    -   GERAN GSM EDGE Radio Access Network    -   gNB Base station in NR    -   GNSS Global Navigation Satellite System    -   GSM Global System for Mobile communication    -   HARQ Hybrid Automatic Repeat Request    -   HO Handover    -   HSPA High Speed Packet Access    -   HRPD High Rate Packet Data    -   IE Information Element    -   IoT Internet of Things    -   IS In-Sync    -   L1 Layer 1    -   L2 Layer 2    -   LOS Line of Sight    -   LPP LTE Positioning Protocol    -   LTE Long-Term Evolution    -   MAC Medium Access Control    -   MBMS Multimedia Broadcast Multicast Services    -   MBSFN Multimedia Broadcast multicast service Single Frequency        Network    -   MBSFN ABS MBSFN Almost Blank Subframe    -   MCG Master Cell Group    -   MDT Minimization of Drive Tests    -   MIB Master Information Block    -   MME Mobility Management Entity    -   MSC Mobile Switching Center    -   NB Narrowband    -   NB-IoT Narrowband Internet of Things    -   NPDCCH Narrowband Physical Downlink Control Channel    -   NR New Radio    -   NW Network    -   OCNG OFDMA Channel Noise Generator    -   OFDM Orthogonal Frequency Division Multiplexing    -   OFDMA Orthogonal Frequency Division Multiple Access    -   OOS Out-of-Sync    -   OSS Operations Support System    -   OTDOA Observed Time Difference of Arrival    -   O&M Operation and Maintenance    -   PBCH Physical Broadcast Channel    -   P-CCPCH Primary Common Control Physical Channel    -   PCell Primary Cell    -   PCFICH Physical Control Format Indicator Channel    -   PCI Physical Cell Identity    -   PDCCH Physical Downlink Control Channel    -   PDP Profile Delay Profile    -   PDSCH Physical Downlink Shared Channel    -   PGW Packet Gateway    -   PHICH Physical Hybrid-ARQ Indicator Channel    -   PHY Physical Layer    -   PLMN Public Land Mobile Network    -   PMI Precoder Matrix Indicator    -   PRACH Physical Random Access Channel    -   PRB Physical Resource Block    -   PRS Positioning Reference Signal    -   PSCell Primary Secondary Cell    -   PSS Primary Synchronization Signal    -   PUCCH Physical Uplink Control Channel    -   PUSCH Physical Uplink Shared Channel    -   QAM Quadrature Amplitude Modulation    -   RACH Random Access Channel    -   RAN Radio Access Network    -   RAT Radio Access Technology    -   RE Resource Element    -   RLC Radio Link Control    -   RLF Radio Link Failure    -   RLM Radio Link Monitoring    -   RNC Radio Network Controller    -   RNTI Radio Network Temporary Identifier    -   RRC Radio Resource Control    -   RRH Remote Radio Head    -   RRM Radio Resource Management    -   RRU Remote Radio Unit    -   RS Reference Signal    -   RSCP Received Signal Code Power    -   RSRP Reference Symbol Received Power OR Reference Signal        Received Power    -   RSRQ Reference Signal Received Quality OR Reference Symbol        Received Quality    -   RSSI Received Signal Strength Indicator    -   RSTD Reference Signal Time Difference    -   SCH Synchronization Channel    -   SCell Secondary Cell    -   SCG Secondary Cell Group    -   SDU Service Data Unit    -   SFN System Frame Number    -   SGW Serving Gateway    -   SI System Information    -   SIB System Information Block    -   SINR Signal-to-Interference-plus-Noise Ratio    -   SNR Signal to Noise Ratio    -   SON Self Optimized Network    -   SRB Signal Radio Bearer    -   SS Synchronization Signal    -   SSB SS Block    -   SSS Secondary Synchronization Signal    -   TDD Time Division Duplex    -   TDOA Time Difference of Arrival    -   TOA Time of Arrival    -   TSS Tertiary Synchronization Signal    -   TTI Transmission Time Interval    -   UE User Equipment    -   UL Uplink    -   UMTS Universal Mobile Telecommunication System    -   UP User Plane    -   USIM Universal Subscriber Identity Module    -   UTDOA Uplink Time Difference of Arrival    -   UTRA Universal Terrestrial Radio Access    -   UTRAN Universal Terrestrial Radio Access Network    -   WCDMA Wide CDMA    -   WD Wireless Device    -   WLAN Wide Local Area Network

1. A method in a user equipment (UE), comprising: obtaining one or moreradio link monitoring configurations, each radio link monitoringconfiguration associated with at least one bandwidth part; determiningthat the UE is to switch from a source bandwidth part to a targetbandwidth part; and performing radio link monitoring on the targetbandwidth part according to an obtained radio link monitoringconfiguration associated with the target bandwidth part.
 2. The methodof claim 1, wherein obtaining the one or more radio link monitoringconfigurations comprises receiving the one or more radio link monitoringconfigurations in a message from a network node.
 3. (canceled)
 4. Themethod of claim 1, wherein each radio link monitoring configurationcomprises: a set of radio resources for performing radio link monitoringwithin its associated bandwidth part, wherein the set of radio resourcescomprises at least one of a Channel State Information Reference Signal(CSI-RS) resource or a Synchronization Signal Block (SSB); and one ormore configuration parameters for performing radio link monitoringwithin its associated bandwidth part. 5.-6. (canceled)
 7. The method ofclaim 4, wherein the one or more configuration parameters for performingradio link monitoring within its associated bandwidth part comprise oneor more of: one or more filtering parameters; one or more radio linkfailure timers; an evaluation period; a number of retransmissions beforeradio link failure is declared; a hypothetical channel configuration; ahypothetical signal configuration; or a mapping function for a measuredlink quality and a hypothetical channel block error rate. 8.-11.(canceled)
 12. The method of claim 1, further comprising performingmonitoring of a downlink channel quality of a first bandwidth part and asecond bandwidth part, the performing monitoring comprising: estimating,during a first period of time, a radio link quality of the firstbandwidth part according to a radio link monitoring configurationassociated with the first bandwidth part; and estimating, during asecond period of time, a radio link quality of the second bandwidth partaccording to a radio link monitoring configuration associated with thesecond bandwidth part, wherein the second period of time at leastpartially overlaps with the first period of time.
 13. The method ofclaim 12, wherein: the first bandwidth part comprises the sourcebandwidth part; and the second bandwidth part comprises the targetbandwidth part.
 14. The method of claim 12, wherein the monitoring istriggered based on an activation rate of one or more of the firstbandwidth part and the second bandwidth part.
 15. (canceled)
 16. Themethod of claim 1, wherein a plurality of radio link monitoringconfigurations are associated with the target bandwidth part, and themethod further comprises: receiving an instruction via downlink controlinformation to use one of the plurality of radio link monitoringconfigurations to perform radio link monitoring on the target bandwidthpart.
 17. The method of claim 1, wherein a radio link monitoringconfiguration associated with the source bandwidth part and the radiolink monitoring configuration associated with the target bandwidth partuse the same radio resources, and performing radio link monitoring onthe target bandwidth part according to the obtained radio linkmonitoring configuration associated with the target bandwidth partcomprises: using one or more of previously-performed measurements andpreviously-performed measurement samples to generate out-of-sync andin-sync events.
 18. The method of claim 1, wherein a radio linkmonitoring configuration associated with the source bandwidth part andthe radio link monitoring configuration associated with the targetbandwidth part use different radio resources.
 19. The method of claim18, wherein performing radio link monitoring on the target bandwidthpart according to the obtained radio link monitoring configurationassociated with the target bandwidth part comprises: applying a relationfunction to one or more of previously-performed measurements andpreviously-performed measurement samples to generate out-of-sync andin-sync events without resetting a radio link failure timer or a radiolink failure counter.
 20. The method of claim 18, wherein performingradio link monitoring on the target bandwidth part according to theobtained radio link monitoring configuration associated with the targetbandwidth part comprises: resetting at least one of a radio link failuretimer and a radio link failure counter.
 21. The method of claim 20,wherein resetting at least one of a radio link failure timer and a radiolink failure counter comprises: resetting a set of radio link failuretimers and radio link failure counters associated with radio linkmonitoring for out-of-synch events; and allowing a set of radio linkfailure timers and radio link failure counters associated with radiolink monitoring for in-synch events to continue.
 22. The method of claim20, wherein resetting at least one of a radio link failure timer and aradio link failure counter comprises: resetting one or more radio linkfailure timers without resetting any radio link failure counters.23.-44. (canceled)
 45. A user equipment (UE), comprising: a receiver; atransmitter; and processing circuitry coupled to the receiver and thetransmitter, the processing circuitry configured to: obtain one or moreradio link monitoring configurations, each radio link monitoringconfiguration associated with at least one bandwidth part; determinethat the UE is to switch from a source bandwidth part to a targetbandwidth part; and perform radio link monitoring on the targetbandwidth part according to an obtained radio link monitoringconfiguration associated with the target bandwidth part.
 46. The UE ofclaim 45, wherein the processing circuitry configured to obtain the oneor more radio link monitoring configurations is further configured toreceive the one or more radio link monitoring configurations in amessage from a network node.
 47. (canceled)
 48. The UE of claim 45,wherein each radio link monitoring configuration comprises: a set ofradio resources for performing radio link monitoring within itsassociated bandwidth part, wherein the set of radio resources comprisesat least one of a Channel State Information Reference Signal (CSI-RS)resource or a Synchronization Signal Block (SSB); and one or moreconfiguration parameters for performing radio link monitoring within itsassociated bandwidth part. 49.-50. (canceled)
 51. The UE of claim 48,wherein the one or more configuration parameters for performing radiolink monitoring within its associated bandwidth part comprise one ormore of: one or more filtering parameters; one or more radio linkfailure timers; an evaluation period; a number of retransmissions beforeradio link failure is declared; a hypothetical channel configuration; ahypothetical signal configuration; or a mapping function for a measuredlink quality and a hypothetical channel block error rate. 52.-55.(canceled)
 56. The UE of claim 45, wherein the processing circuitry isfurther configured to perform monitoring of a downlink channel qualityof a first bandwidth part and a second bandwidth part, the processingcircuitry configured to perform monitoring further configured to:estimate, during a first period of time, a radio link quality of thefirst bandwidth part according to a radio link monitoring configurationassociated with the first bandwidth part; and estimate, during a secondperiod of time, a radio link quality of the second bandwidth partaccording to a radio link monitoring configuration associated with thesecond bandwidth part, wherein the second period of time at leastpartially overlaps with the first period of time.
 57. The UE of claim56, wherein: the first bandwidth part comprises the source bandwidthpart; and the second bandwidth part comprises the target bandwidth part.58. The UE of claim 56, wherein the processing circuitry is furtherconfigured to trigger the monitoring based on an activation rate of oneor more of the first bandwidth part and the second bandwidth part. 59.(canceled)
 60. The UE of claim 45, wherein a plurality of radio linkmonitoring configurations are associated with the target bandwidth part,and the processing circuitry is further configured to: receive aninstruction via downlink control information to use one of the pluralityof radio link monitoring configurations to perform radio link monitoringon the target bandwidth part.
 61. The UE of claim 45, wherein a radiolink monitoring configuration associated with the source bandwidth partand the radio link monitoring configuration associated with the targetbandwidth part use the same radio resources, and the processingcircuitry configured to perform radio link monitoring on the targetbandwidth part according to the obtained radio link monitoringconfiguration associated with the target bandwidth part is furtherconfigured to: use one or more of previously-performed measurements andpreviously-performed measurement samples to generate out-of-sync andin-sync events.
 62. The UE of claim 45, wherein a radio link monitoringconfiguration associated with the source bandwidth part and the radiolink monitoring configuration associated with the target bandwidth partuse different radio resources.
 63. The UE of claim 62, wherein theprocessing circuitry configured to perform radio link monitoring on thetarget bandwidth part according to the obtained radio link monitoringconfiguration associated with the target bandwidth part is furtherconfigured to: apply a relation function to one or more ofpreviously-performed measurements and previously-performed measurementsamples to generate out-of-sync and in-sync events without resetting aradio link failure timer or a radio link failure counter.
 64. The UE ofclaim 62, wherein the processing circuitry configured to perform radiolink monitoring on the target bandwidth part according to the obtainedradio link monitoring configuration associated with the target bandwidthpart is further configured to: reset at least one of a radio linkfailure timer and a radio link failure counter.
 65. The UE of claim 64,wherein the processing circuitry configured to reset at least one of aradio link failure timer and a radio link failure counter is furtherconfigured to: reset a set of radio link failure timers and radio linkfailure counters associated with radio link monitoring for out-of-synchevents; and allow a set of radio link failure timers and radio linkfailure counters associated with radio link monitoring for in-synchevents to continue.
 66. The UE of claim 62, wherein the processingcircuitry configured to reset at least one of a radio link failure timerand a radio link failure counter is further configured to: reset one ormore radio link failure timers without resetting any radio link failurecounters. 67.-88. (canceled)